You need to realize that you are a good person and need self-worth before going to far into a relationship. "Love yourself before loving others."

I like what JJBX said too, negative feelings are a sign of something wrong most of the time. Embrace them and think back on what maybe causing them and then put a positive thought in place of them. It doesn't seem you are very aware of your feelings and thoughts.

It helps putting yourself in a calm place and relax. Do some self reflecting and it will help you see more clearly.

Also here are some helpful website, I think I am dating a guy that has similar thoughts which I'm thinking of sending these websites to:

The Difference Between True Love and Unhealthy Obsession

How to Have a Healthy Relationship