TMI

Hi all, my fiance and I have been trying to conceive since my last period (Feb 14th). We almost have sex everyday, pretty good sex life. With our first, I got pregnant the one and only night we accidentally tried. Since then I have had brain surgery and been on so many medicines (I've been off of them for over a month because I was trying to get ready for this month). We tried 2 times in December and it did not happen (I was also still taking my medicine then) but.. I feel like maybe I'm just not fertile anymore, i was on some serious pills and it worries me so much. But this past few days I've had some slight nausea, is this maybe a VERY early pregnancy sign or just a bug and I'm getting over my head by overthinking it? I'd love some honest answers.

Also, been cramping and tired more than usual lately. And my discharge has been on heavier side.