Light spotting 5 weeks 2 days

Hello! I just recently found out I was pregnant this is my first pregnancy so I'm a bit nervous, today I woke up to a very light pink faint spot when I wiped as I Pee'd should I be concerned? No pain or cramping just that faint spot. It happen a few days ago one time then didn't happen again until today. Should I go to the ER? Me and my boyfriend did have sex last night could that be it? Nothing rough or crazy lol just normal basic sex bc he's worried he'd hurt me. I have an ultrasound schedule for sept 21st which would be my 7 weeks.