No matter what I do ...?

After I eat the first meal of the day my stomach feel full or bloated. By full I don't mean my hunger is gone. About a month ago I had terrible stomach cramping and went the doctor who diagnosed me with a UTI, even though I had no symptoms such has pain when peeing or going more often. I had a CT scan done, which led me to see a GYN who did an ultrasound. The only thing found were very small cyst nothing out of the ordinary. I also had flank back pain and have trouible standing for a long period of time because of my stomach. If anyone could help that woul dbe great. Since the doctors aren't helping me out much. I am also 19 and female if that heps with anything