Im going to ask my doctor next time i go in, unless it goes away. But i was wondering if anybody else had experienced this

Under my left armpit, i have this sore lump, it started on friday as just being a sore spot, but last night i noticed it was now a sore lump. It only bugs me when i touch it, and im not quite sure what it could be. There is no redness so i dont believe its an ingrown hair, because i shave my armpits lol. But it worried me at first. I stupidly googled it and it said breast cancer?

Ive never been around cancer before so idk if thats something they have to specifically test for, or idk how they even test for cancer, so im not sure if that would be something that showed up on any of my blood tests. Im currently 25 weeks pregnant and i saw some articles about it being a clogged duct, so i have no idea what it could possibly be. Any advice would be appreciated. Tia