Why have I been called back

I had some discharge from my left nipple that I thought was blood , had a scan and doc tuck sample of discharge and doc says it wasn’t blood was more brown . He was happy and said to monitor discharge and go back in 4 months . Iv now had letter 4 weeks later changing my appointment from in 4 months to e to next week , what could this be

Call your GP and ask them, saves worrying yourself sick for a week. If they won’t discuss it over the phone, then firmly ask for immediate appointment to discuss. Best of luck x

Do you think it is possible that they have found somthing in the discharge or would of been spoted sooner as it’s been 4 weeks