As Anax said, it may go away and may not, but the best is to try to get used to them. As long as you let UE know and they are OK with you trying to work it out you should be fine. You don't want to needlessly send them in, but then you don't want to be stuck with something that doesn't fit properly or you have to pay to fix later.
Although, with only 30 minutes that does seem like you need a refit. I would try to lubricate the shells before inserting which may help. I know that depending on the shell, some custom IEMs can hurt when inserting until the develop a layer of natural lubricant!