pcos letrozole question

hey ladies I'm a married 28 yo going through fertility treatments. I'm on letrozole but for some reason when we b/d it feels dry or burny down there we tried preseed for the first time thinking letrozole was making me dry as a well known side effect. Still burned... when I went to wipe some lube out there was a bit of blood . the b/d wasent rough and neither of us have any stis any answers at to what this could be 🤷🏻