375mg of Test-E is not TRT. Did you mean to post this in Pharma: https://forums.t-nation.com/c/pharma ?
At 250mg Test-C I was taking .25 adex twice a week. When I went to 500mg, I used .50 twice a week. I think I would've been fine with .25 at 500mg, but I didn't feel an E2 crash or anything. I'd rather be safe than sorry. As for your knees, do they feel like they need to be "popped" or just general aching? Did you just start cardio?
E2 crash is no joke. You will know when it crashes. For the last two weeks or so, my entire skeletal structure (joints) feel like the need to pop, but none hardly do. I crashed my E2 out of paranoia. Lesson learned.