I smacked my 50 lb puppy and i feel so guilty 😢

Guys I am sure I will just get a lot of hate from this post, but I really just need advice.

I have an 8 month old mutt Ollie (argentine dogo/hound) who is 50 pounds. Have had him about 5 months. I also have a 6 year old chihuahua and Italian greyhound.

We did ALL the training, immediately. Ollie was extremely obedient up until a couple weeks ago, when he suddenly gained a ton of strength and energy overnight (destroyed the couch, ate the drywall). He gets 1-1.5 hours exercise daily just btw. He is so amazing overall and so well taken care of.

For the first time ever, he hurt one of my small dogs that got too close to him while he had his favorite toy. My little dog screamed out because he has bitten too hard, only Ollie didn’t even clock it. Without thinking, out of pure motherly rage, I instantly smacked him and had to drag him outside by his collar when he played dead. He is indestructible and I didn’t hurt him at all. But he did look very upset with me.

I have raised two small dogs and NEVER even swatted them, not once. I would never hurt an animal. This 50 pounds of terror is just a whole other ballgame, it’s extremely hard to explain how much rougher this dog is even though he is soooo sweet. How else should I handle this situation? Besides the obvious positive reinforcement when he’s playing well with them. BTW, little dogs and Ollie are never left unsupervised together!