He was fine chewing on a toothbrush with a smear of paste, but clamps his mouth shut whenever I tried to do it. I was worried that his teeth weren’t getting brushed properly and so a friend recommended an electric toothbrush for babies which I tried this morning. He absolutely hated it, started crying hysterically and now won’t even chew his normal toothbrush or put it in his mouth. He currently has four teeth. What am I meant to do?