So it’s fat and squishy and you heard a pop?
That’s happened to me 4 times. 3 out of 4 times I needed arthroscopic surgery. Hopefully you are in the lucky 25%.
Well I’m just another online doctor wannabe so take my advice with a grain of salt:
Since you don’t have health insurance, just do ice and elevation. Ice 20 minutes on, 20 minutes off. Ibuprofen every 4-6 hours. Get that inflammation down and out. For the love of God do not put heat on it. That’s only for sore muscles. Something is bleeding, thats why it’s fat and squishy and purple. The good news is that all that will reabsorb on its own. Probably take a week. Ice and elevation. Keep your knee above your heart as much as possible.
Go very easy on it for a week or two. If it gets better on its own, count your lucky stars because you probably just had a sprain. If it doesn’t get better or you get what I had (more on that later) or it randomly locks on you, then you will need a doctor.
So, how did I know which times I needed surgery? Well the first time they didn’t know what was wrong with me. At first they thought torn ACL, then they thought torn menicus, so they scoped me to repair the meniscus. They got in there and found the meniscus was fine but there was a piece of cartilege the size of a quarter just floating around my knee.
The second and third times I knew because after the swelling went down I could occassionally feel a hard lump of cartilege sticking out under my skin. Gross feeling. It’s called a “joint mouse” because it’s like a mouse running around under a carpet like in old cartoons. 
Good luck. Ice, elevation, be easy for a few weeks. Hope it’s just a sprain.