He should see a vet so try applying for care credit which is a medical bills credit card that is accepted at vets offices as well. If you can get it take him to a vet he probably has a uti males can be prone to them. You can also dilute apple cider vinegar with water and get him to take some of that which can help clear any sort or crystals in his urinary tract. If he is on dry food switch him to wet food to increase his fluid intake. Cats get most of their moisture from food. Make sure he continues to pee regularly. If you see he stops peeing he must go to a vet immediately.
Make sure he continues to produce urine. If he is straining and producing none then that is a critical emergency. Get as much water into him as possible including watered down canned food and absolutely no dry food.
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