Interesting. Can you post a newer picture if you get a chance. I imagine its probably gotten quite a bit bigger now.

I'm not so sure it's a pumpkin, it's so yellow and just staying yellow like a crookneck. But the shape just totally throws me off. The other plant I let grow is so much bigger but it's not setting fruit like this one.

Odds are it is a mongrel. Squash are very promiscuos. It does seem to be a bush or semi bush form with the shape of a pumpkin. The C.pepo varieties of pumpkins cross readily with summer squash most of which are C.pepo..

Mongrel lol. I love it. Is there any risk in eating it? As long as I can eat it, I'll let it grow. I'm guessing semi bush. It seems to set out a couple of vines from the central point which some of the vines stay short and others are really sprawling. Has very curly tendrils spaced along the vines.

Those look like Jack Be Little to me.
I grow them every year. Wait until they reach a deep dark orange before harvesting.
You can use them as decoration or for eating. They taste delicious!

I think you're right Lorelei80. They stayed small (jack be little size) and started turning orange. The vines are almost all dead so it must be soon to harvest. I wasn't sure if I should wait for the stems to turn brown or if I could harvest before then, but I figured it doesn't hurt to wait. I doubt they'll last to fall but it was fun growing them.

If they stayed small, then I'm almost 100% that they are Jack Be Little. You can go ahead and harvest them as soon as they turn a dark orange color.
A few tips that may help you, they will last a very long time after harvesting if kept in a cool dry place (such a mold free cellar or garage). Store them sitting on a newspaper on a shelf, but don't let them touch each other.
I'm not exaggerating, I had some last for 6-7 months this way. I grow them every year because they are so tasty and they make perfect serving sizes! If you want a squash like side dish for dinner or your kids (grandkids?) want a snack, then all you have to do is cut them in half, scoop out the few seeds, lay them on a lined baking sheet, add some butter and cinnamon if you like, and bake until tender.
The pumpkin taste is very intense on these tiny guys and I prefer them hands down to any other type of larger pumpkin or squash. The benefit is their small size as they are always sitting there, ready to be popped into the oven and feasted on!
Good luck :)

Sounds yummy, they may not make it to fall because they'll get eaten. Turns out quite a few got attacked by bugs or other damage from where they contacted the ground. Thanks for your help! I think I may purposely grow them again.