Help?? Brown clots 8+6 weeks 😰

Hi, I was wondering if anyone can share their experience as I can't stop worrying!! I'm 8+6weeks and for the past few days have had brown discharge and sort of stringy clots when I wipe!! It happened again last night after I had an upset tummy!! To begin with there was no cramps but now I'm having consistent back pain and twinges in my tummy, I phoned nhs but they told me not to go up unless the blood was red ? Any advise?