You are not going to get any definitive answers here. You need to see a doctor for proper testing and treatment. If you are still having problems, then you need to follow up with your doctor. Penis sensitivity cannot be conclusively be determined to be caused by an std.
I took some antibiotic, single dose of azithromycin. About 20 hours ago. The one thing I'm really worry about is that my penis head really sensative.
You should have it checked out by a doctor. It is possible it is a UTI. Or it could also be NGU. It is a sexually transmitted bacterial infection that cannot be classified as chlamydia or gonorrhea specifically.