Could Inflammation Of Rectum Be Due To Intake Of Medicine Post Expiry Date?

Hi ..my name is Peter...I'm 28 ..about a year ago ...I accidentally drink a 2 year expire med..is liquid...since then I start have problems with my stomach ..all systom I have is almost almost like hemorrhoids or ulcerative colitis.. mucus come out when I use the stool ...burnings sensation in my rectum to my anal..when I pass gas mucus also come out ..urge to go bathroom 5-6 time sometimes nothing come out just gas ..but I feel better after but it come in 20 min..my weight keep go up and down...what wrong with me?