I used to use anabolic steroids 3years ago. I stopped using after getting a swelling in my thig were I injected the steroid. I am still getting this?

The most logical. Deduction is that the swelling is inflammation. You may have seeded an infection there if you didn't wipe top of bottle off when pulling into syringe or there was a contaminant in the liquid. You may have a pocket of infection that waxes ANS wanes or say a foreign body from the injection if u used a big needle. Next time it swells, go in and see if do thinks it looks infected. Gd luc.