stubborn industrial!!! >:(

Keegan

i got my industrial a year and 3 months ago, and sometimes it just.. RANDOMLY swells! not like an icky, discharge kind of sweeling but just..swollen. its not red, or itchy, or sensitive. just swollen for a week or less and then it goes away! its really annoying and fairly ugly to look at sometimes lmao. and suggestions as to why this is happening or how to prevent it?