I have anorexia and when i try to exercise my abs and the muscles i work swell for about 1 to 2 weeks and i don't know what to do or what that means.

? muscle strain: which can happen to non conditioned individuals, you didn't mention whether your muscles become sore as well? you need to be coached well, high protein diet and warm up before exercise, a coach would guage the approprite exercises for your habitus and nutritional status together with a dietician. If still suffering follow up with your doctor, best wishes