Three Weeks Ago,i Had Terrible Pains In My Stomach,slightly Loose

Three weeks ago,i had terrible pains in my stomach,slightly loose when i went the toilet,followed by a pink discharge, for the next 4 days. My stomach was very bloated and painful.Last night ,it was very swollen again and hurt. I just assume im going through the change,as im a 52 yr old female,do i go to the doctors or not, my grandma had stomach cancer,so im just a bit worried,my stomach is bigger than it use to be,and im not eating anymore.