I am 24 and female, i have not been feeling 100% for quite a while now, and feeling really fed up because of this.

firstly i had what i thought was a urinary tract infection, with burning and stomach and back pain, this seemed to pass without treatment, then a couple of days later the burning seemed to return but would pass within the day, this happened a couple of times, then i had a random case of diarrhea (watery) just the once, I had a panic attack following this but everything else was fine other than feeling tired and under the weather, so i stopped eating and drinking anything that would set it off again including alcohol. Now its two weeks later and i had another random case of diarrhea this time it gave me the chills and kept me in bed for 3 days, i didn't have anymore diarrhea but i didn't eat anything other than toast and chips, i have a constant discomfort in my abdomen, rumbling, gas sharp pains that are on and off and indifferent places it also feels like its burning, i have had a normal bm but noticed mucus when i wiped. I still have back pain aswell

I have been to the GP and had blood tests and a urine sample but didn't give me anything, not even antibiotics for a possible UTI ? which i thought was odd as if it is a kidney infection i have had it for 3 weeks untreated?

can anyone shed any light?