Moving from a college to sixth form

I want to leave my college and move to a sixth form, since I absolutely despise the environment and wish for a more serious education. I have contacted many sixth forms since January, but they were all either full or they told me to call back in September. I'm scared that even by that time they wouldn't have space and I would have to be stuck in my college for the next 2 years, which I cannot bare to think about. It makes me feel sick to my stomach every day. How should I approach this situation?