Ongoing stomach/digestion problems

Hi guys, after ongoing stomach issues I'm posting here to ask advice on a problem I have. Sorry about the long read but hopefully it gives enough information for you to give some suggestions.

As background I had a urinary tract infection from last November, finally clearing up in June of this year. Before this I was otherwise in good health.
I am now 26, and of a regular weight, eating reasonably healthily. I did until a few weeks ago like to drink at weekends, though in the last 2-3 weeks I have gone completely teetotal in a bid to beat my stomach problems. I also currently play football once a week for an hour for excersise.

Around the time of my infection I did have a doctors appointment explaining my stomach concerns and I was told I have indigestion, and that due to my age I shouldn't really be worried. This concerned me as serious problems can develop in younger people too! I spoke to a friend of mine who is studying to be a doctor and he also tried to re-assure me, and commented that during my antibiotics I could have developed a peptic ulcer without being aware of it.

I had 5 sets of 2 week antibiotics from November through to the end of June, gradually rising in strength until June. Around February though I began to see some stomach problems ranging from severe to mild, all of which were explained to the doctor. Blood tests were done which were clear and a test for loose stools was also cleared. For note, since then stools have been usually lighter in colour than usual, and on occasion I feel a burning sensation when passing these.

Due to the indigestion during this time I took some indigestion medicines. I experienced severe reflux around this time after eating spicy foods and citrus drinks, and on one isolated incident I felt like vomiting straight after eating without actually doing so. This has not happened since though. Around March time I developed a lack of appetite directly after taking the antibiotics and the Gaviscon/indigestion tablets. I also started using probiotics which slowed my digestive tract down.

OK so fast forward to today, the urinary tract infection is minimised, though stomach problems remain. The main symptom is a lack of hunger. I can go hours without eating as I generally do not feel hungry. I usually eat anyway, as I realise I will become fatigued if I do not. As a barometer for this, I ate a small meal on Friday evening approx 5pm, and after a long lie in til Saturday lunch time, at 1pm I was still not hungry at all. Just to confuse matters though, on the odd occasion (last being yesterday) I will have a normal day becoming hungry around lunch and dinner time. This is fairly rare at the moment though.

Other symptoms include feeling of light/medium pressure in lower left front ribs usually in a morning, this can be accompanies by a gnawing pain after a meal. I do not get reflux any more. One way of describing when I wake up I can feel my stomach inside me, and it feels kinda rubbery. After a large meal I am sure there is some inflammation below my sternum, the area becomes slightly raised, and then returns to normal after a short while. Again when doctors felt my stomach they found nothing out of the ordinary.

I am not in any real pain, more mild discomfort and the lack of hunger. Could I still be feeling the effects of the antibiotics or could I be looking at something more sinister/serious that requires further investigation?

Thanks again