Constant headaches and tiredness

Aw

I’m 18 weeks and 4 days and for the last 3 days I’ve had a constant headache that I can’t shake I wake up with it and go to sleep with it. It’s not super painful most of the time but it’s just there niggling away. I’ve been napping after work and still sleeping like 8/9 hours a night and still feeling tired. Has anyone else experienced this? If it continues I’ll call my GP and hopefully get an appointment for Thursday which is my day off.