The medication you are on can certainly have sexual dysfunction side effects - notably the Zoloft. I would consider adjusting some of your medications - you may want to consider Wellbutrin, which can have less of a sexual side effect.
If adjusting the medications does not help the problem, tests including testosterone levels, and urological evaluation (i.e. IVP, cystoscopy) can be considered to evaluate the difficulty with ejaculation. I would suggest a urological referral.
Followup with your personal physician is essential.
This answer is not intended as and does not substitute for medical advice - the information presented is for patient education only. Please see your personal physician for further evaluation of your individual case.
Thanks,
Kevin, M.D.