Good for you for trying something new. It's discouraging with diabetes to see an endless string of bad BG numbers with roller-coaster changes.
I use a low carb diet that overlaps Paleo quite a bit. Where my diet differs is that I eat dairy. I use heavy cream, yogurt, and cheese. I've been on this diet for a year and a half and it's been wonderful. I lost weight, feel better, and my blood sugar is much easier to control. Not magically wonderfully perfect, but much better than before low carb.
I totally had to overhaul my insulin regimen. The first thing I needed to discover was a new basal profile that corresponded to my changed way of eating. I used this method to adjust my basal rates.
I also made many changes to my insulin to carb ratio and my insulin sensitivity factor. MY total daily dose of insulin was about cut in half.
With lower carb meals I found I had to dose insulin based on protein and fat as well. Search this site for posts under the group "TAGgers United." It's an inactive group but I got a lot of ideas about how to use extended boluses to cover protein and fat. I give myself an immediate bolus for the carb content of the meal and then give an extended bolus for the protein and fat. I could give you more details if you're interested.
My life changed for the better when I started to eat fewer carbs. Not everyone can stick with it, but it makes so much more sense than trying to eat all the carbs you want and then giving yourself huge doses of insulin. Fewer carbs = less insulin = smaller mistakes.