Knee injury and afterwards

Honestly none of us can give you a good answer, especially as you've had zero imaging done. I realize this isn't the answer you want but it's the truth. You don't have a diagnosis and none of us can diagnose you. With a diagnosis you would potentially be able to get some educated guesses from people here who have experience with knee injuries/rehab, but even then those would be educated guesses.

In terms of exercises, OrthoInfo has a useful page here and another potentially useful one here. Ideally you would be talking with medical professionals (and not the internet - even if there are people who are medical professionals who are also speaking with you over the internet despite you not being their patient), but as you said, you don't have insurance.

Those are all symptoms that suggest you should see a sports doctor to find out whats wrong and your options. And if you cant afford a doctor or pt, you can live with it lots of people live with major knee injuries but they are prevented from doing the activities they like, or they continue and keep doing more damage. The choice is yours.

For what it's worth, on the other side of that coin - I once fully dislocated one of my patellas in my late teens (I was probably 19 at the time). I didn't have PT because my GP was irresponsible and didn't refer me for (or even suggest) PT. Fast forward maybe 5 years and I was experiencing pain when cycling which shouldn't be happening to an otherwise physically healthy person in their early 20s. Turns out I needed major surgery to avoid major cartilage damage (I would have eventually needed a double knee replacement had my surgeries not been done) and then a second set of surgeries some odd number of years later, which wasn't so much the fault of my original surgeon so much as it was an issue of research advancing.

Had I not had surgery I wouldn't be able to continue cycling (unless I wanted to deal with moderate knee pain for the next 5-7 days), running would have been completely off the table, swimming would have been so-so (even front crawl), using the elliptical (which isn't my favorite thing ever but it's useful for warming up) would have been out, and so on. It also would have been a very quick road to needing a double knee replacement. Note - I really enjoy doing activities that involve bending my knee, regardless of whether or not they are high impact so not being able to do those things is a fairly big deal for me.

I'm not sure whether or not having had PT when I first dislocated my knee would have allowed me to avoid knee surgery, as the issue was that my patellas tracked in a very abnormal way, but I probably would have been able to put them off for longer. I've since had loads of PT from various very good physical therapists (most of whom are cyclists actually).