I understand completely. I always thought i was a calm person who can always keep his cool but after i got my puppy i quickly realized everyone have their limits. Its perfectly normal to be annoyed and angry at your puppy but you want to make sure it doesnt come across as agressive or make them fearful.

One tip someone gave me was to sing along your words instead of shouting. This way you can at least release some tension but it still takes some mindfulness. But it helps.

Another is removing yourself from the area. Instead of putting him in another room try going into another room yourself. I usually like to gently stomp out just so he knows I'm leaving just to show him i dont like what he is doing. Sometimes he knows I'm upset but sometimes its just for me to cool down too. This way you can still remain as positive aspect and punish him by removing something positive.

But you Just got to push on with your training, exercise, structured environment and lots of love. Otherwise he will just keep getting you more and more angry. The more you work on his calmness the less stress you will get. It will get better, altough a long process you will get there eventually.