Many popular medications have sexual side effects, and new medications with sexual side effects are introduced every year. Ultimately there is no substitute for discussing your concerns with your doctor in a frank manner, and returning to inquire about alternate courses of treatment if the current one is causing sexual dysfunction or distress for you.
It's important to remember that even if you live in a small town your doctor still has a medical degree, and is unlikely to be shocked or embarrassed by any reasonable question you might ask.