I think i have bowel cancer or maybe colon cancer? what do you think?

I think i have bowel or colon cancer because i have been having a really hard time going to the bathroom lately. I have been like this since nov, i started with constipation every now and then and then as the months went by it started hurting more and more to go to the restroom, i bleed bright red blood from my anus and i find it in my stool. The last 1 month have been the worst, i have had excruciating pain when i go to the restroom, i don't go to the restroom for approximately 4 to 5 days :/ which is horrible :( last friday i drank a magnesium citrate bottle and it helped me for the day, although my stool came out as diarrhea it still hurt and burned like hell!! on sunday i found a hemorrhoid and i have been putting preparation H. Since sunday i have been drinking Metamucil 2 times a day. since sat the only day i went to the restroom was on wednesday, only because i did an enema wash but even that didn't help, my stool didn't come out the way it was suppose too. I have lost a big amount of weight the past week and my appetite has dramatically reduced, my stomach always just feels uncomfortable, and is always hurting. This includes drinking lots of water and eating very healthy each day, especially eating a lot of fruits. :/ im really worried and i know i have to get it check out, but my parents don'tt always take it too seriously, it just worries me the most because im only 16 ;( so yeah i have tried everythingg from laxatives, to washes, stool softenersrs everyday, to fiber cereals and now the fiber drink but nothing is working, i really cant handel the pain anymore i cry every time. whats your guys opinion? please and thank you:)