You do have our energy!

But it comes out in different ways.

When you laugh at our jokes, or respond (in or out of character) to our banter, or lean in with keen interest during an epic monologue, you feed our energy with yours. I can't get into a back-and-forth with a brick wall; even if you just laugh and describe what your character does instead of acting anything out, if I know you're having fun with it that gives me the mental fortitude needed to keep acting ridiculous.

Being the only one in character is one thing, it's a little awkward at first but once everyone knows it's your thing it's fine, but if you're the only one in character and everyone else just kinda deadpan responds it's an instant vibe kill. If there's someone in your party that is always in character, even if nobody else is, that means you make them feel comfortable enough to express their character, and that isn't nothing! I know they appreciate you letting them channel their character.

Yeah I feel you. I'm doing two campaigns right now, one is my first time as a player and the other is the first time as a DM haha, as a player I'm a bard so the face of the party and my old-school improv skills are getting tested for sure!

Personally I find fleshing out your character's backstory makes playing them a lot easier. If you know your character inside and out, you don't have to translate an event into their "language" and think about what they would do or say from their perspective, you just let the thing happen and the character will tell you how they respond.