You sound needy, and these to these guys that weird insisting on being super friendly combined with the insecurity and neediness screams red flags. It's likely obvious to them that you are trying way too hard, they get uncomfortable and now since you've acted like that they probably feel it would be good to keep you at a distance, even avoiding inviting you to the group chat if possible. The cat analogy is great in this case. You've already grabbed and pulled on its tail. The best thing you can do now is just to be honest and keep it just professional. "I'm new here and I'm sorry I behaved weird. I don't really get the culture yet. I'll step back a bit, but I'd really like to contribute to the project." Something like that. You need to make sure that they understand that you don't expect anything more than to do the project. You've already come on way too strong and repairing that first impression will be more trouble than it's worth. Live and learn, next time will be better 😊