What is happening to my body?! Please help!

[keb5325]

So I had unprotected Sex on 10/13. I have no idea when i ovulated and my cycle is very regular. My period was due on the 15,16 or 17. I didn't get it until the 19. It lasted 2 days and was fairly light, no clots, sorry for the graphics! Now I am having weird discharge sometimes milky white, sometimes watery. I have been a bit nauseous, dizzy at times, kinda crampy, crying a lot, very tired.
To make things more complicated, I have and am being treated for a sinus infection which could explain some of the symptoms but I'm looking for reassurance.
There's no way I could be pregnant, right? Btw I'm 39.

[ootus973]

If your period was due on the 15th, you probably ovulated around the 3rd. Generally, you can't get pregnant just before your period is due. You need to have intercourse right at ovulation time or just before. The egg doesn't live very long after ovulation unless it's fertilized. Your discharge could be due to the meds for your infection.

[hotpinkmomma0811]

I'd test just to be sure for reassurance honestly.