i am 68 years old, married and sexually active. i can still achieve an erection but it seems more difficult to experience an ejaculation. i have taken3 tabs of melatonin 5mg.,1, 800 ibuprofen on nights that i exercise, weight lifting, walking 1and a half- hours 3 times per week. losartan, triamterene, metoprolol, atorvastatin are medicines taken now as a result of a cardio infarction. is my inability to experience ejaculation or orgasm due to my taking to much melatonin or ibuprofen?