Having time by yourself to relax is just as important as having lots of fun things to do.
You can do this best by being in a quiet, comfortable place like your bedroom. You could put some relaxing music on in the background and if you have any sensory lights put these on too.
Try not to think about anything you are worrying about and completely relax.
The things you have to do will still be there later and when you have spent time relaxing you will be more able to sort them out as you will be refreshed!