As we always say, a picture would help. Some pines are incredably tough and others snap like popcorn. Virginia, or Scrub Pine that size are quite safe. A White pine that size might snap right off. If you are going to pull yourself up over one of those limbs, make sure the rope goes over the limb and then comes down on both sides of the trunk, not just over the limb. You want the weight pulling back into the crotch, that way the shear strenght is considerable. If the rope goes over just the limb and walks out just an inch or so the shear strength drops fast, every fraction of an inch equates to more leverage to snap the limb off. If you are climbing limb to limb keep your feet in as close to the trunk as possible. I like to think if the limb is green and healthy and the size of a ladder rung, I can climb it, but keep your weight in tight, even if your foot is kinda sideways wedged into the crotch.
I'm making a huge ass-u-me-tion (assumption), and by the way your question is worded, I'm probably wrong. Do you have a safety belt and know how to tie in with it? If you don't, DO NOT try to climb the tree and use the rope you have tied around your waist as a safety. If you slip with a rope around the waist it can crush your diaphram and render you unconcious in about 15 seconds. Many tree stand hunters die every year by having safeties tied around the waist. Please take no offense, since I don't know you I have to plan for the worse and hope for the best. Be careful, Joe.