While experiencing side effects is particularly common during the first few months of being on the pill, you can experience side effects at ANY time on the pill. Unless it keeps happening and becomes a nuisance for you, I wouldn’t bother changing pills. You do have a risk of experiencing worse side effects on a different pill if you switched. Also you are not guaranteed to have the same experience on that pill now that you did years before.
I personally regularly experienced breakthrough bleeding before and after break weeks on several pill brands.
Side effects are not reflective of the effectiveness of the pill so no that’s not true.