Should i take a blood test

My love & i have been TTC for 9weeks now. My periods come like clockwork each month well this month i didn’t get my period on start date 2/12. Instead on 2/11: i started having light cramps & spotting only when i urinate nothing on my pad 2/12: i had some dark brownish red blood but it wasn’t much 2/13: it was back to spotting only when i urinate then nothing since. I’ve been having all the other symptoms that goes along with pregnancy. Took 2 test & both said negative. Confused & need help