Newbie needs accountability

Hi! I'm Emily and I join MFP five days ago. I waited to see how it works for me before I make a fool of myself--I mean, introduce myself. I just weighed myself today and I've lost 3.4lbs! I don't know if you can tell, but I'm pretty ecstatic about this fact.
Here's some background on me:
-I live with my parents because
-I go to the community college nearby because
-I did a dual high school/college program while I was an upperclassmen and I need to finish up my associates degree before transferring.
-I'm taking 15 credits and this does affect my eating habits
-I have four younger siblings whose metabolisms are a work of art and are in no way eating healthy
-I was in denial that I was overweight for a long time because I used to play soccer and "muscle weighs more than fat."
In other words, I have no one to keep me accountable at home and I could really use some support here. I'm also eager to support others, as I'm going to college to become a school counselor.
Thank you!