Mine has been doing the same... I thought that the movements were supposed to slow down in the third tri.. but mine are just getting stronger and more constant. I even said to DP yesterday I hope there is nothing bothering him which is making him wriggle more!! Paranoid I am hehe.
It's not uncommon for me to be walking through the shop and all of a sudden be doubled over clutching my belly or my side due to a swift hard jab or roll.. gee I must look a sight, but really, this baby doesnt know the meaning of 'gentle'!!