Skin concerns related to intermittent breakouts

It is not a frequently occurring symptom.

Sometimes, small bumps or hives appear on my skin.

Sometimes it itches too.

It doesn't spread, but it comes up and then stops. What could be the reason for this?

Should this be treated as a skin lesion?

It really bothers me that it pops up every now and then, just when I'm about to forget about it. It's really bothering me because it's appearing on my face too.