4 days late

4 days late and a negative over the counter pregnancy test...feeling frustrated because I'm not in great health and take daily medications that would not be safe for the baby. Not sure if I should stop taking and risk harm to myself or risk the possible growing baby instead...can someone please give advice? Is it too early to be registered on a home test? I really didn't mean to get pregnant, like I said my health is not good. Not sure how this happened or what to do.