So I'm growing Burpee Early Sweet Sugar Pie Pumpkins and I have two plants that are now 43 days old, both of them have a main vine that's about a foot long and I am just starting to see the flowers. When I look towards under the leaves in the center of the plant I notice more growth points. Are these (circled in red) more main vines or just secondary vines?

Also, if anyone can find a blog or video online of someone growing these pumpkins please post the link.

Thanks for your help!