Hi! How long have you been working out? If you are doing weight lifting, it could be from your muscles swelling, although 4 pounds is a lot! Is it close to AF? Could be water retention (temporary) from increasing your water. Are you watching the amount of sodium your are eating? I know when I first start working out, and if I am working out hard, I will gain a bit before I start loosing. Also, don't cut your calories way way back, below 1200-1400. If you go too low, your body will hold on to every calorie and will go into starvation mode, which defeats your purpose.
I am sure others will be around with ideas/solutions!
I am also doing Paleo/Primal as well as following the Whole30 for my first month or so. I am looking at recipes and I agree with a few changes, I think the recipes will work. Just no shakes for me--going to stick with eggs and veggies for breakfast. Would love to follow both of you if you would like a new follower!