Everyone's going to tell you something different. The general consensus should be if there are veins still lining the egg, the bird needs to stay in that shell for about 6-12 hours longer. 8 hours after initial pip isn't very long at all. If I'd helped after that, my babies would surely have died. The struggling, if not excessive, is good exercise for babies.
High humidity during hatching is crucial. If you have a small styrofoam incubator, I suggest taking out the plastic liner and wire and putting down a moist towel, hatching in a plastic bin lined with paper towels. The moist towel on the bottom creates a lot of surface area of water, and it will not evaporate quickly. While I don't suggest taking the time to change your incubator's environment during a hatch, you may want to do that next time. If the membrane is drying out, wet the visible membrane and wrap the egg in clean paper towel, moistened just slightly with warm water. Don't cover up the pip.
I did this with my baby and she basically popped out.