A couple of suggestions:
1) it may be that the pain you are experiencing now is from the stress & strain put on your muscles from retaining all that food & then from getting rid of some(most?) of it??
2) it may also help in general if you "massage" your large intestine, this "muscle" often retains alot of the watse it's supposed to get rid of & tthis builds up & causes a blockage (which certainly seems to be at least one part of your problem) - now it really is better to see this "massage" but i'll try & describe it; start with your hand (or fist if easier for you) at your lower right groin move hand slowly but quite firmly up to base of ribs then go straight across to the left side under your ribs & then down to lower left groin (this is the position - & direction the food takes - of your large intestine, this "massage" has worked wonders for my daughter who has suffered constipation since birth. Do it several times & several times a day.
3) I would go to a search engine and type in questions alomg the lines of: what causes ammenorrhea (or is it dismenorrhea?) (missed periods) other than pregnancy & menopause? Or what medical conditions cause periods to cease? Also what medical conditions cause severe constipation?
My daughter was misdiagnosed with anorexia nervosa last year, despite being atypical & looking up symptoms on a search engine helped us alot, she's now getting better with a sane & sensible dr who listened & tested for other possibilities. In her case being on the pill for 4 months caused her periods to cease totally (11 months later she still hasn't got them back) & also caused severe weight loss & stress overload which also caused further weight loss.
So I would also suggest you seek other opinions & maybe visit an ob/gyn.
