Light pink spotting

Addison

So I had this small amount of spotting one time today it is light and only when I went pee.

My period is typically 24-28 days or so. My last period was march 29- April 2

I had sex on April 6th and 7th

I’m thinking i ovulated on april 11th or 12th.

My period is due somewhere between 4/21-4/25.

Can someone tell me what this could be?

Also I had a weird red hot ears, face and chest that almost looked like a rash today.

Thank you all