Passing out.. Concerned

Hillary • I work at a hospital in Panama City. I am lucky to be with my best friend and love of my life, Michael Hernandez.
Hello ladies, so I am in my fertile window, finished my last BC pack as I should, had my cycle and joined glow when my first menses was comple. Long story short I was BDing with my DP in the shower today and I was getting out and began feeling lightheaded. I've been nauseated all day and I want to believe it was the hot shower and activity that got to me. 
I have never passed out in my life. When I go to work tonight I plan on getting checked out. I have an appointment on Wednesday with my OBGYN to get blood work and make sure I am good to go for TTC. Just advice would be appreciated.