I had one like this just this week that pipped on the wrong end.
Just watch it closely, and make sure it can get air through the hole it has made. If more than 24 hours goes by with no progress on the pip, then VERY carefully you can 'zip' the egg shell. I do that first, leaving the membranes intact. Work as quickly as possible to reduce the chances the membranes will dry out while you have the bator open.
If then there is no further progress after another couple hours, you can try peeling back the membranes VERY slowly. Stop if there is bleeding and put the egg back in the bator for a couple hours and see what happens. By that point you will probably HAVE to help it out the rest of the way as all the opening and removing the egg will dry out the membranes. I've found that the more you 'help' the more you HAVE to help.
Peel a little back every couple hours, stopping if you see blood. I will peel all the way around so the chick can then work it's own way out of the egg when it is ready.
Good luck!