The difference between my head voice and chest voice is too big?

First of all, I'm 14. I don't like my head voice. It's too quiet, no matter how hard I try. I use it only to sing high notes, but when I change from chest voice to head voice, it's easy to notice and my chest voice is louder than my head voice. I like to use chest voice because it can really 'fulfill the room' and it sounds really nice, but when I must start singing higher, I start using my head voice and it sounds squeaky, it's not loud enough and it's weak. I don't know if it has to do something with puberty.

I didn't take any voice lessons, and I won't take them soon cause they cost like 100$ per hour in my country. I'm a part of a church choir and everyone compliments me when I sing, but when I need to sing higher(often), everyone says I just need to be louder. I can't be louder no matter how hard I try, like I said.