hi welcome to hcm forum
as per your history you have UTI and now you have joint pain and muscle pain
... With UTI you can have joint and muscle pain. I would advised that the antibioptics you have started you continue the full course of it If the infection is not getting control then you get your urine culture senstivity test and then start the antibiotic course as per sensitivity test result. and take lot of water.
wish you early recovery