Mima, the bugs are sow bugs which eat dead vegetable matter and debris. Not a big problem, but if you have them, you may have other critters, too. You definitely will want to get rid if your mulch. (What Hetty said) After your bloom season, I'd get a large clean planter, or clean yours thoroughly, and carefully unpot your plumie, and remove all the soil from it's roots and inspect the soil for tiny fungus gnats larvae..almost microscopic tiny white bugs in the soil. Hopefully there won't be any.
Then you'll want to repot your plumie in a good plumeria mix. I use a blend of cactus mix and perlite with the recommended amount of Nutri -Star time release plumeria food and a few Tbs. of bone meal mixed in well. These aren't necessary, they're just what I use in my mix. After you repot your plumie, you'll want to only water it lightly maybe once per week or so, when your top 3-4 inches of soil feel dry, or when the pot feels light (in weight) . My opinion only...
...and, in the meantime, I'm dying to see that first bud unfurl....looks kind of like a yellow or white, maybe?
