I've never had any problem with my teeth before like swelling and bleeding. could it possibly be pregnancy? and i've been getting headaches a lot..

Pregnancy gingivitis: There is a condition called pregnancy gingivitis. Hormones produced during pregnancy can cause the gums to swell and bleed. Strict oral hygiene is very important during pregnancy.

Possibly: But gingival inflammation in and of itself does not indicate pregnancy. Have yourself tested to see if you are pregnant or not if you want to know for sure.