(Concern) My knee has been repeatedly bothering me since I injured it.

Last fall, I went to the hospital because one of my knees was very swollen, and I was diagnosed with a partial tear of the anterior cruciate ligament. I wore a brace for almost three months, had fluid drained, and received injections. After that, I felt a bit better, so I did some rehabilitation and knee strengthening exercises, but even though I didn't think I was overexerting myself, my knee swelled up again. I thought it would get better with rest, but there was no improvement, so I had the fluid drained and received injections again. Currently, the swelling has gone down and I can carry out daily activities without much trouble, but it doesn't feel completely normal like the other knee. I understand that I can't fully restore the knee's original condition and that I need to build muscle and strengthen it, but even a little leg exercise feels burdensome, which is frustrating. I'm wondering if I should just rest and avoid overexertion for now, or if I should actively seek rehabilitation methods and do something about it.