Hi there,
I have dealt with severe OCD related intrusive thoughts before, usually homicidal ones but I also struggled with intrusive thoughts about being a psychopath. Here is what I've learned over many hospitalizations and lots of good therapy: If you are bothering to ask and post about whether or not you are a psychopath, it's pretty much a 100% chance that you are NOT one. A true psychopath would likely never join this forum and would certainly not be concerned about their lack of empathy - that would just be how they are and would see nothing wrong with it.
The fact that you are so concerned, worried and remorseful shows me that you are a good person, but dealing with some intrusive thoughts that make you feel otherwise. I have been there. I highly recommend a good therapist with whom you can do exposure therapy. That is how I overcame my issues, and at one point I was told by my psychologist that I was one of the worst cases of Pure O he has ever seen. It can be done.