If I read correctly you have a plane that has the wing already joined and 5-minute epoxy was used to join the wing. If this is the case then you will be just fine with it. While it's not how I would have built the plane (I would use 30+ minute epoxy), but the wing is more than likely going to be just fine the way is. And I can assure you it's not going to be worth the hassle of trying to cut the wing apart to re-do it with 30 minute epoxy. If the wing is already joined the give it a good tug to ensure that it's well bonded and then fly it.

Now if the wing halves haven't been joined yet, then yes you want to use 30+ minute epoxy to join them with.

Ken