constipation is getting in the way of everything!

I am ALWAYS constipated! I'm only 16 so I have school, band, sports, etc.. and constipation is getting in the way of everything! I spend atleast 20-30 mins on the toilet trying to go to the bathroom. Ive changed my diet to high finer and I drink water as much as I can. But I still have complications. Its uncomfortable and my abdominal area looks bloated all the time and I rock hard from being unable to go to the bathroom. Ive also tried eating prunes and even look up different ways to sit on the toilet. I'm sick of these constipation complications. HELP ME.