I've had diarrhoea and constipation on and off for a while now have lots of yellow jelly in my poo feeling like i need more a lot of cramps had mrsa?

IBS: Sounds like Irritable Bowel Syndrome, which can diarrhea, constipation or alternate between the two. It can also cause bloating, cramping, mucous in the stool. Doesn't have anything to do with MRSA.

Probiotics: Unclear from your question if you had mrsa. If you did, the antibiotics probably killed good bacteria in the bowel leading to this problem. Probiotics are available without prescription that can re populate your GI tract. Also eat foods that are easy to digest such as rice, banana, avoid natural laxative fruits such as cherries, plum,,peaches, apricots, increase bulk foods like kale, oats, bran.