help, do i go to hospital?

i'm on the pill, i skipped my period that was due on christmas and had it a couple weeks later instead & it ended 5 days ago. yesterday i felt very sick like i was going to throw up & i thought it was stomach bug but when i went to the toilet there was brown discharge on the toilet paper. i thought nothing of it thinking it was old blood but a day later, i feel mildly sick and just went to the toilet to find it's EVERYWHERE!!!! leaked through my pants. i have ' possible endometriosis ' and hashimotos hypothyroid which can cause thus but i am on medication. what do i do? help.