There are some papules on my glans.

Hello, your condition is probably infected with foreskin GT inflammation.

Erythema is a typical symptom of foreskin GT inflammation. In fact, infection is not necessarily spread through others. It's hot in summer now, because of bad hygiene habits, if you don't pay attention to local hygiene, you will be infected. If the foreskin is too long, because the foreskin cavity is warm and humid, it is conducive to the reproduction of bacteria, so it is more susceptible to infection.

The pearl rash you mentioned is a kind of foreskin GT inflammation. However, if pearl rash is not treated, there are also risk factors, that is, pearl rash is easy to become cancerous. So I suggest you go to the hospital to make sure your condition has not deteriorated.