I just now looked again: All the pumpkin flowers are closed up, but, it looks like new ones are on the way. No sign of fruits yet, and the plant has been flowering for a bit over a month, I believe.
So... a bit of artificial insemination is in order. I hope the pumpkin plant does not belong to a sect whose beliefs are offended. /s
How long does it take for the fruits to fully develop once they begin to form?
A LONG time. Pumpkins are usually 100+ days on the seed packet. Don’t worry, you’ve still got plenty of growing time by you.
Make sure you keep them watered each week in your heat! Also, if you can give the vines some shade, they would appreciate that. (7a, Right?)