Get Rich Quick Scam

Sooo... I quit my job in Feb and have been doing freelance gigs to help with bills since then. I posted a resume in CL and a guy responded saying he needed someone to keep an eye on his house since he's an architect and leaving the country for a few weeks. Cool. My salary was $400/mo to do general PA tasks like answer calls/emails, run errands, and ship/receive on his behalf. Sounded totally legit.

So the guy says he's sending me a company check to purchase some blueprint supplies, which are very expensive, and I'll be responsible for getting them to his house. Cool. Easy pie. Two days go by, and voila, check... Only it's for almost $2000, and its addressed to ME!!!

Did I mention I never met this guy before in my life?! I txt him immediately cuz I'm concerned, he says it's fine, just deposit it. Keep $400 as we agreed, and use the rest to order his supplies. I'm TERRIFIED cuz the check looks like somebody printed it off their computer, but my boyfriend is like "that's fine, people do that", so I googled it and sure enough, legit.
So then I google and LinkedIn the issuing company- real estate and title services since the 90s. Cool! Things are lookin up!

So I deposit the check at the counter with my ID. The girl scans it, types some stuff, blah blah blah, and it's okay, only they had to hold it over the weekend. I'm shocked!!! It was fine, not a scam! ...so I go grocery shopping with my available funds win win.

Dude texts me every day, and I'm thinking it's because he trusted a stranger with his money. I reassure him I'm not a crook. I'm grateful and happy to oblige, I needed this.

Weekend passes, I get the money and he says that instead of ordering the supplies, just send it to his boss... In Nigeria. Huh?!

Whatever. I'm happy, I'm at Anscot, things are going smooth till the teller gives me the side eye, and I'm like THIS *kitten*! lol. And then she asks me what my relationship is to the person Im sending the money to is, and I can't help but wonder why it's her business, and tell her so. My uber is outside waiting for me, this guy is on the phone waiting for his money, and Miss Slowpoke wants to play 20 Questions. Then she gets on the phone with corporate and 20 minutes later is sliding my order slip and my cash back through the window because they refuse to serve me. I ask her if she would've sent the money if the recipients were white. She rolls her eyes.
I wa SO mad. I apologized to the guy, had my driver take me Walmart and leave o_O (he was happy, but I that was the most expensive trip up the block I've ever taken! Lol) So I'm in Walmart, my phones dying, I'm apologizing to the guy, and then he tells me to tell them he's my brother... Wait, huh?! Until this point, I hadn't done anything wrong. I was filled with righteous indignation at the poor customer service I received, but other than my exiting smarminess, which I felt she earned, I hadn't done anything WRONG. Why lie if I don't have to? I go to the counter to pick up a money gram sending form, and there's a HUGE warning about sending money to people you don't know, and sending money to Nigeria, and it all sounds kind of familiar... So my stomach flip flops and I know something is wrong.

I walked outside, sat on a bench and called my auntie (cuz my mom would kill me). She's flipping out, she thinks it's drug money, the Nigerian cartel is gonna start sending her body parts if I don't get it to her and part of me wants to laugh, and the other part is getting scared, thinking maybe I should take the money and run! Lol
I consider calling the cops, I consider putting the money in an envelope and shipping it, and the whole time I'm worrying what to do, the guy is texting me, freaking out about his money he thinks I stole -_-
I'm so embarrassed. How did trying to find a job land me in this mess?!! Good going Nya! Lol.

My phone died, so I walked to the bus stop. I know the driver saw the thick stack of 20s rolled up in my wristlet while I fished for singles to pay the fare. I feel like a criminal.
When I got home, I looked up "Nigerian Scams" and sure enough, they send fake checks. So I called my bank and explained the situation. The teller told me to hold the money for another just to make sure it's legit. I text the guy that my phone is back on, and I'm sorry, but I can't send the money for another week. He's pissed I'm hoping he doesn't kill me... But then he threatened to tell the FBI and I giggled, realizing he probably WAS in Nigeria.

I turned off my phone and forgot about it... Until this morning. My account is overdrawn -_- the freakin check was fake!! And I woke up to instructions for yet another address to send the money... I told him where he could put his instructions and counted the wad... I'm short the price of a wasted uber, groceries, and lunch. If I deposit the money now, my account will be negative until I can hustle up the difference, but I can't even GET to jobs without cash, so what do I do? I'm aware it's not my money. I feel sick. It's not the bank's fault or problem.

My initial thought is to return everything but $100, so I can get to work and take care of things next week until my boyfriend gets paid... But I feel guilty. I considered using some of the money to buy sponges and buckets, so I could have a car wash and hustle up the difference this weekend (and maybe make a profit?) But again, ITS NOT MY MONEY!!!
I'm conflicted between doing what I know is right, and making sure I have what I need to get by.

What would you do? It's only 6:13pm. I can still get to the bank, but busses only run until 10. Every transportation option requires spending money. My boyfriend isn't home. No help, just me. I'm open to all opinions and advice.