What could this be? Should I go

Stephanie • 25 year old 💁🏻‍♀️ - Married 💍 - Pregnant with my 1st (Baby Girl Due December 8th💕🌸)

Yesterday, I found out I was pregnant. I should be around 4-5 weeks. Husband and I had sex last night and I woke up to this. What could this be? Should I go to the hospital? No cramping just spotting. Still feel nauseas and breasts are tender. Also I have a headache!