Should I get a blood test ?

I do have inregular periods but they have a pattern aswell for example il start at end of a month changes dates every month and if I miss a month I always start 1st if the next month and have two periods that month so one at start and one at end my last period was August still haven’t started I’m 34 days late says glow I could be less or more as I am inregular , iv took some tests and all negative I went to doctors for a test ( urine sample ) and that came back negative , do you think it’s worth having a blood test dine just incase ? Never ever been this late it’s normally a couple of days iv had tingly nipples and cramps every now and then and been having headaches and feeling really tired aswell