hCG will shut down your HPTA (so will exogenous T). the hCG acts like the LH and this will stimulate testicular T secretion. T metabolizes partly in estrogen and this provides the feedback to the pituitary → shut down
If you want to stay fertile and need to increase T its:
either Clomid only (no hCG or exogenous T) - which will stimulate the pituitary (and not shut it down) to secrete more LH and FSH
OR
hCG (with or without exogenous T) to stimulate spermiogenesis and if this is not enough then you add FSH