It sounds like she has a urinary tract infection. I would have a vet do a urinalysis. If this is normal then here is my usual answer to this type of question:
It could be a number of things. The first thing you should do is take her to the vet for a urinalysis to rule a urinary tract infection out. If that is good then pursue the following. Have you changed brands of litter? Sometimes they will not use the scented kind. If you have changed and this has started then go back to the one that the cat liked. If you have not changed it you may want to try an unscented one anyway if you are using scented. They may have changed something in the scent. You also need to be sure the box is cleaned every day- more often if you have a multi cat household. They do not like a dirty box. Have things changed in your household to upset the cat? Have you gotten another pet, a new baby, had a lot of company, been gone yourself? You can try using Feliway from the pet store. It works on pheromones and makes the cat calmer if it is under stress for whatever reason. It is certainly worth a try. Also get some of the special cleaner to neutralize the smell of her urine on the areas where she likes to go. It is called FON at the vets or by different names at the pet shop. There are several different ones available.Last but not least there are prescription drugs that may help if it is a behavioral problem. You need to ask your vet about these.If you found this helpful please remember to accept it.
As far as the bowels it could be stress, parasites, or food related. Start with the urine first as this needs to be taken care of asap and ask your vet about the stool issue while she is there.
If my answer was helpful please click the green accept button My answer should not take the place of a Vet's diagnosis when needed. Positive feedback is most welcome and a bonus-though not required-is greatly appreciated no matter how small.