so i had protected sex about three or four weeks ago. my period was late so i took 4 pregnancy tests all different brands. they all came out negative. i got some blood today and i'm assuming it's my period. the blood is like brownish and light. am i just overthinking it ? or can it be something else. when i was putting in the tampon i took it out and red blood was on it. am i okay? and also i've been stressed about it for about two weeks now.