Can someone please help me find out what my knee injury is, how to treat it, & how long the recovery time is?

so here's the story......Last year...maybe a year and a half ago, i injured my knee doing a leg workout for basketball but i don't have the luxury of going to a doctor to find out what it is. So i've kept playing basketball and now its starting to hinder my explosiveness. All i can say is that all of the pain is located at the bottom center of my knee cap or patella. My guess is that it is a moderate to severely strained patella tendon. However i do know its not a ruptured/torn patella tendon cause my patella is not all the way up into my thigh. I am still not sure if it is my patella, my ACL, or my Meniscus. i have looked at several pictures of the muscular/ skeletal anatomy of my left knee, and im still not sure that kind of injury it is. if anyone can help me.....please cuz im dyin here cuz basketball is something i wanna do for the rest of my God-given LIFE.