Tore my MCL?

A little backround about me; I'm 18 5'10 walking around 230 now with this injury since it doesn't let me do much, let alone squat.

I practice Brazilian Jiu Jitsu and Box as well, hoping to become a fighter, that now seems iffy. I got this injury in my knee, and I don't remember how I got it. I felt no pain at all. I don't remember no popping anywhere. One day I just felt my knee really sore, and I thought it was because I was barely breaking into BJJ, as it was my third weak. I experienced all types of soreness, all the way from soreness in the ribs to cramps in my legs. It was pretty normal to me. It went by a week and I noticed the pain was the same, and the pain was getting slightly worst. I also noticed my knee was swollen. It was swollen in the right area of the center of my knee, like if you look at it from a "looking down at your knee" perspective. It was pretty swollen, I could tell easily and by others as well.

I started researching and came to the conclusion that it was an MCL injury, due to some site giving me information on the difference between and MCL injury and an ACL. Here's a timeline of the situation

November 2011- Injured knee before Thanksgiving, was experiencing pain and soreness till the end of the month. My knee locked up really bad and could not bend it.

December 2011 - Swollen knee and walking stared to become difficult. It lasted almost the whole month and I was limping and I couldn't work, I needed to work. Knee still locked up.

January 2012 - I could walk again beggining of the month, and by the mids I was walking normally. By the end of the month the pain was also fading and my knee was feeling great. I could bend my knee now 75% better but still felt a painful sensation when stretching my knee outwards.

Feb 2012 - As of right now, I can walk and run pretty a little more. I can do things like involve my leg at a faster pace now, I can bend it inwards no problem. The problem right now is that I feel pain walking upstairs and upstairs, mostly because the squatting part I cannot do completely. It hurts to squat. Thing is, at some points in the mornings, I can walk stairs normally with no pain. The pain come and goes really.

Why I haven't seen a doctor? Unfortunately for me, I have no insurance for a doctor, and I can't afford one. Am I stupid for doing this? Yeah, but I have no other choice. I'm sure an MRI would clear up a lot of things but I can't afford it.

Also note in all this months, I have not done any rehabbing exercises, mostly because of the fear of injuring my knee again with a sole bad twist I make without being aware. Some help, feedback, advice, even consolation would be greatly appreciated. Thanks for your time reading.