"Misdiagnosed Twice!"

In the last 3 months I have unfortunately had to go to A&E 4 times. The first for a severe migraine by which they put me on fluids and sent me away with Naproxen and Co Dydramol. It was clear after 2 doses of Naproxen that my stomach was not reacting well to it, so I phoned 111 and they ordered me an ambulance for severe stomach pain. Whilst there they said I must've just pulled a muscle and was put on Tramadol, the medication my father was on when he had bowel cancer. The next night having stopped taking the Naproxen and starting the Tramadol my pain was no better, so again I sought advice from the NHS' OWN 111 service who again sent out an ambulance for me. Upon arrival at the hospital having waited for a few hours I was told that nothing was wrong with me and I was simply constipated, despite opening my bowels the previous day and no tests other than simple observations, and the pain not being associated with anywhere except my stomach (ie. no lower abdominal pain) and was told to stop taking such strong medication and stick to paracetamol (despite the fact they prescribed it to me). Having done my own research I suggested perhaps I had a stomach ulcer, and the A&E doctor laughed in my face and told me to not be so overdramatic. I was discharged that night at about 2am and in agony still, with no diagnosis other than constipation which I knew was wrong. I went to my GP 2 days later as the pain was unbearable, who after 15 minutes of poking my tummy and listening to my symptoms diagnosed me with a stomach ulcer and I was put on Omeprazole, which eased the symptoms and put me out of discomfort. (My GP is back on the coast in Hampshire as I have only recently moved to London and had not changed yet so I had to go home for a diagnosis. My trips to A&E were under the advice of the NHS). Then this weekend I was feeling not myself so had a relaxed weekend avoiding too much action and pretty much staying in bed, however yesterday I had worsening back pain, concentrated urine, nausea, pain and inability to pee and when able to barely any comes out etc. so again I phoned 111, the NHS advice line that you are told to ring if you have any concerns about your health and again I was advised to make my way down to A&E. Upon arrival I was waiting for hours, they did no basic observations (BP, HR etc.), didn't take blood and merely asked for a urine sample that I was struggling to give them as I couldn't pee very easily despite drinking over 1.5 litres of fluids that day. Eventually over an hour later of trying to pee I managed to pee enough to half fill the pot and handed over my sample to the Dr, who did a quick dipstick (I know the reliability of those can sometimes be flawed as I used to work in a hospital myself) and said nothing was wrong so again sent me off with Co Dydramol saying I had flu, despite having no flu like symptoms. I shall be seeing another Dr today and I am very sure my diagnosis is a kidney infection as this will not be the first time