I am not sure if exercise will help, depending on your symptoms. It didn't help me.
You bg and insulin needs increase throughout your preg. It's very possible that what you're experiencing is normal, and you should talk to your doc. My 1st I got very discouraged (more insulin injections needed each week). This, my doc said, was normal throughput the course of the preg. Talk with your doc, but it sounds like you're progressing through the preg in a typical fashion. Good luck!