HELP???? Husband having mood swings?????

I don't know what the heck is wrong with my husband. We are a young married couple with 2 kids. Overall we have a very good marriage. We do bicker and fight sometimes (not a ton) but nothing major and usually its over stupid petty things. This morning its like I woke up to another man. I've never seen him rage and get as angry as he did EVER in my life. It was over the stupidest thing, he didn't agree with why I put our 3 yr old in timeout (she was standing on the kitchen counter about to jump from there to the couch) He pulled me into another room and a full out fight ensued, ending with him rearing back like he was going to hit me (HE DIDN"T HIT ME) he walked away promptly after rearing back like he was going to hit me. Even though he never hit me It scares me, I've never seen this side of him. I dunno even where to start in handling this, I know something needs to be done.