Please Tell Me If This Is Normal.......

So, my bf and I are ttc #1 and have been trying for a couple months, this month is our 3rd try and the past couple months we've just been having fun, not stressing about it but this month we decided to really give it a go. We started trying the day after my period ended, my fertile week hasn't even started (we are just gearing up for it) and we've dtd 3 times in about a week and I'm feeling so sick. I have a headache, I'm nauseous, and just don't feel good. Obviously I'm not pregnant but does anyone else experience this!? Honestly we haven't had sex this much in such a short time period. Hoping it doesn't get worse, we have another week or so of dtd ....... Could it just be my body reacting to having so much sex or is this a dumb question? Lol. Idk!!!!!!!