Hello.
Thanks for writing to DoctorSpring.com with your health concern.
Pregnancy after a tubal ligation is very rare.
It can be easily ruled out by a pregnancy test if you are doubtful.
Following childbirth, periods are irregular in many women.
Also, weight gain is obviously common too.
The abdomen takes time to come back to the normal shape.
You need to put in dedicated exercise and follow a strict diet regimen.
I would ask you to have the following investigations anyway -
1. Pregnancy test.
2. Pelvic scan to rule out any lesion in the uterus or ovaries causing the menstrual symptoms.
3. TSH, Calcium, Vitamin D levels.
Regarding diarrhoea, take a lot of curd, yoghurt and a daily dose of probiotics in your diet.
Give yourself atleast 6 months for your body to recover from childbirth and come back to its normal self.
Are you breastfeeding ?
All the best.
Please feel free to discuss further.