Late thin watery period

im almost two weeks late for my period and i've taken pregnancy tests, although they all came out negative i've had symptoms and signs of pregnancy. I've just noticed i'm bleeding, but i don't know if it's my period or not because it is very thin and watery. I've googled it (which i know i really shouldn't do because it makes me scared about my health) and ive seen that it can be spotting during pregnancy or could mean i have a deficiency in something.

Does anybody know what it could be and/or have experience with this?