Have lower left abdominal pain. Had Normal colonoscopy 2 yrs ago, No diverticulosis or anything. Could I have developed Diverticulosis in last 2 years?

Many possibilities. Ovary, hernia, uterus, bladder are all possible sources of your pain. Constipation is easily remedied at home with bowel regimen, increased oral hydration and laxatives. If no better, get in for appointment with your regular doc. Be well.