Hi Ashnant
Constipation after birth is not unusual.
It is caused by the abuse your bowel and intestine have taken during birth. Normally your intestine pulsates. This pushes the waste matter along the intestine. After birth your intestine can become a little bit lazy and not pulsate as well as it should. This in turn gives more time for your body to absorb more fluid from your poo making it harder and thus leading to constipation.
Coloxyl and senna tablets are a great idea. You can buy them over the counter. They contain a stool softener and a bowel stimulant.
Other ideas are pears with the skin, prunes, lots of water, exercise.
Also avoid bananas they can contribute to constipation