Kitten Scratching and Pushing at door

I have 2 kittens, and they are brothers, about 6-7 months old now. One is much bigger than the other. The big one is very sweet, but he is also the more needy kitty. And he really doesn't like closed doors. It's always him stretching and meowing when I have my door closed, his brother doesn't seem to mind. I'll even feed him, play with him, and when I go to shower he is immediately scratching at the bathroom door too.

For 2 weeks I did the training were you ignore scratching at the door. I would wait until he stops and walks away, then I redirect him to play with his toys or his brother. Ive been off work because of the snow storm. Yesterday I played with them for an hour, napped with them, cuddled with them, we hung out for like 8 hours. Then I wanted to play video games, so I went to my room and closed the door. It wasn't even 30 minutes and he was scratching at my door and throwing a tantrum. Usually he does this when his brother disappears downstairs, but that wasn't the case. His brother was there, he had food, water, and plenty of toys. I went ahead and changed the litter and redirected him to his toys.

15 mins passed and he was throwing another tantrum. I lost it that time and picked him up roughly. I was mad because he won't let me play my games for just a bit without needing something. I decided to have another play session with them. But even after that, 1 or 2 more times he was scratching and meowing at my door.

This morning, he woke me up scratching, pushing, and meowing at my door. He didn't stop for 30 mins, so again I was upset and picked him up roughly. I don't understand why he is behaving like this now. But it seems the training isn't effective with him.

Any advice?