Why do I feel like this after sex?!

So my husband and I have been trying to have a baby for about a year now with no luck. We’ve been together for 6 years. Every time we have sex (which is quite often, about 5 times a week as we are trying to have a baby) I feel nauseous for an hour afterwards so I just have to lay down. Which makes it hard to wan to have sex sometimes because I know what’s waiting for me afterwards. Does anyone have this issue?!