My Husband Gets A Feeling Something Is Going To Happen

My husband gets a feeling something is going to happen he then gets an upset stomach, sweats a lot and all this lasts only 10-20 sec. It happens every two months and will last for two days. He may have only two in this time frame or he may have as many as 30. Yes, we have been to our Dr. who thought is was his ears. Went to a ENT who said it was not his ears. Did a Diabetes test and an artery test all came back normal.