Can I sue my landlord? I have been dealing with snake issue, mice issue, and now toilet sewage backup for 5 months now

The new landlord came in Feb. I'm March we found snakes in our basement. It was over the weekend and the property manager did not respond until Monday morning. She accused me of bringing them in. I have nothing in the basement. They were coming through drain vent. Exterminator came out put down glue traps. That didn't help still came in. We put a rock on the drain. We still have mice. They have done nothing about thst. We had to buy mouse traps and board up the area where we though they were coming in. Still getting in some how. Landlord has done nothing about it yet. Today the toilet ran over. Had to turn the water to it off. Now have sewage backup. Had to go and get supplies to get the smell out and clean up the water. Landlord said she will send someone on Monday possibly. Then she said if we are unhappy then why don't you just move. What can I do.