He might also get angry. Peter has a strong sense of justice. If he feels that the Avengers are being unfair, he could stand up to them. He'll use his quick wit and his powers to show that he's not going to be pushed around easily.
One possible reason could be a misunderstanding. Maybe Peter accidentally gets involved in something that looks bad to the Avengers, like being in the wrong place at the wrong time during a security breach. So they misjudge him and are mean as a result.
It could also be due to jealousy. Peter might be getting too much attention from the public or other superheroes. His youth and new - found popularity could make the more established Avengers feel overshadowed, leading to feelings of resentment towards him.
It could be that Peter's immaturity showed in a crucial situation. He might have been over - confident and tried something really risky without thinking it through. The Avengers, being more experienced, would be frustrated with his recklessness and thus yell at him. They want him to learn and grow, but his actions might have been too much to tolerate at that moment.
They might notice signs like Peter being overly withdrawn, flinching at sudden movements, or having unexplained injuries. Maybe they see him constantly on edge around certain people.
Peter might be very defensive at first. He could argue back, trying to explain his actions. After all, he is a teenager with his own ideas and he may think that the Avengers don't fully understand his perspective.
In some fanfics, Peter might faint due to overexertion. He's often depicted as being involved in intense battles or using his powers to the extreme. For example, if he's been fighting a powerful villain for a long time without a break, his body could just give out and he faints.
I'm not entirely sure what 'ex' means in this context. If 'ex' is short for 'experience', it could mean that Peter has some sort of experience within Avengers fanfiction. Maybe he's a character in a fan - written story and has had certain adventures or relationships within that fictional universe.
In fanfiction about Peter, the Avengers are often central to his story. They can act as his safety net, always there to catch him when he falls. Their presence in his life can change the way he views himself and his role as a hero. He may feel pressured to live up to their standards, or he could be motivated by their trust in him. Moreover, the relationships he forms with individual Avengers members, like his friendship with Ned which might be influenced by the Avengers' team spirit, are important aspects explored in such fanfictions.
Obviously, Peter Parker is one of the main characters. And then, the Avengers members like Tony Stark, Steve Rogers, Natasha Romanoff, etc. are also main characters as they are the ones adopting Peter. They play important roles in Peter's new life and in the overall story.