Insane amount of pressure in my head when I bend over etc

So I noticed this when I was pregnant, my son was born in October 2017... whenever I’d bend over, I would feel an insane amount of pressure in my head and I’d have to stand up quickly to relieve it. A few days ago, I woke up with a headache that wrapped around my face like this:

..

and every hour or so I’d get this pound of pressure throughout my head as if my head were a drum and someone hit it with a drumstick. The pressure has definitely increased and I can even feel pressure in my temples while sitting normally now. I also feel pressure when I lay down flat without a pillow. Has anyone else experienced this or have any idea what I should do about it?