Maybe get a muzzle. If my dog ever gets nippy I put her muzzle on and she'll whip her head around and try to scratch it off but if she calms down and relaxes I'll take it off. Also if she's jumpy and gets to excited or hyper I'll kennel her up. But it has to be for a good amount of time like 5-10 minutes, and when I let her out if she's still crazy I'll put her right back in. And for 15-20 minutes. Think of it kinda like a kid in time out if he's going to be unpredictable he gets kenneled, like time out. I usually tell my dog she's in time out and she'll whine and try to get my attention but when she's in time out I ignore her. Because why should she be rewarded for being bad, you know? He'll learn that if he wants more time out of his kennel he has to behave.