What exactly did you do??
Many many Christians have this fear, because they have questioned things, which is normal. I too feel the same way because I was involved in a highly charged supernatural spiritual event that many said was the devil and many said it was the holy spirit and I was in the middle.
I think if you did, you would have felt the Holy Spirit leave you or you would have fallen and back slid so hard that you would be freaking out, and I am not sure if yo go to hell even if yo do do so. I think you are not rewarded or can go to the higher levels in heaven.
Fast and pray for the Holy Spirit to be filled in you.
Maybe Satan got into your head and is freaking y ou out.