Yup. That makes sense and you can say like that, but in writing, you gotta change 에 to 의.

So close. 안녕하세요!! 정말 팬이에요!! 요즘, 리메인즈의 노래가 머릿속에 박혀있어요! 정말 대단해요! (More casual 진짜 짱이에요 it means you are really awesome)

Hmmm... I can understand the sentences, I don't know well, but the sentences are not the everyday way people usually use. Maybe because of the way of using some particles, endingand words? I would write like this: 안녕하세요! 전 진짜 팬 됐어요! 요즘, 리메인즈의 노래가 머릿속에 박혔어요.정말 대박이에요!