Need help with my snake!!!

[Juggalette]

I jst got my snake and it shud be time for it to shed. It stopped eating and it's eyes turned grey but now it's acting very funny. I checked on him and he was upside down. I can't really afford to take him to the vet right now unless it is an absolute must. I'm pretty sure tht this is not normal. He's still crawling around but not like he used to. Be keeps trying to roll over. Some one plz help asap. Thnx