Cum tastes strange doesn't it?

I've been giving my boyfriend bj's for a while now. Most often when I know that he is about to cum, I finish him off with a handjob and clean up with a tissue or towel, only really tasting his precum. I've been lately letting him cum in my mouth. His cum tastes real funny, I can't describe it, just off. He also cums a lot and I'm having trouble swallowing it, there's to much of it and it tastes and smells rank? Am I crazy? Do you think that there might be something wrong with him, or is it me? It's very rank, lots of it, and smells and tastes wrong.