Trust your instincts, if, and only if you have a track record that shows that your instincts are right in most cases. The truth is, there are a lot of other things that can trigger anxiety and panic outside of being instinctual.

Not knowing what your patterns are, your typical reactions to things, I would not jump to the conclusion that this is the case.

Do you have a pattern of running away from something that seems too good to be true? Do you have the expectation consistently that says the worst will happen? How do you view yourself, do you expect women to be trustworthy or not? Look at yourself and consider whether this is based on habitual fears or if it's based on reality.

On the surface at this point, I would say you're pointing out it went well without highlighting any warning flags so likely it's based on a fear of either it "not working out" or other things that would make you expect the worst.