Hello,
Thank you for your query at DoctorSpring.com
I understand your concerns.
I need to know the names of the medicines you took before commenting. The only medicine that can turn urine red is Nitrofurantoin, but that is an antibiotic. Also, I will still suggest you to get an urine culture done, because infections can't be treated with OTC drugs. It can rather ascend up and cause further problems.
Hope you understand,
Regards.