Started losing weight quickly and recently stopped but one thing I noticed is I haven't had a bowel movement since Friday and I've eaten a ton of food but still only maintained my weight.

Should I be concerned or ask my doctor? I recently had what appeared to be an onset of MS like symptoms with mainly lack of muscle definition, which previously existed, and during this period I lost a lot of weight.

I don't feel full or bloated but I'm concerned because prior to this year (literally 2015) eating food would cause weight gain and I always needed to maintain a diet and exercise to keep it in control. Since this year I haven't worked out and started losing weight rapidly until I increased my calorie intake to ~4k/day. Since Friday I stopped losing weight but I also stopped having any bowel movements.

For example Monday I ate eggs and bacon for breakfast, a grilled chicken salad for lunch, a whole large pizza for dinner, and probably 4 candy bars for a snack.

Any other time in my life and I probably would have had to loosen the belt and would kill my toilet the next day.