How to know if you are scared of commitment?

My friend persuaded me to try online dating and I found a nice guy. He's a little older than me and I found out he is a commitment minded guy and has had real relationships and isn't trying to just fool around. We spoke on the phone for a long time and set up a date. He told me he enjoyed talking to me and asked if it's ok if we talk a little more before the date. I said it is fine if we talk more. We both said we are looking for relationships not a fling. He seemed very sincere and legit. I know because I've dated many guys who were not good. He texted me a bit. Just nice things like how are you doing. He isn't blowing my phone up or anything. I did like him on the phone.

So why do I feel a little nervous in my stomach when he texts me? I really did not spot any red flags. I've dated a lot of jerks and guys who were emotionally unavailable (not men who were in commitments but ones who refused to commit to anyone). Sometimes I wonder if I have commitment phobia. Whenever I meet new guys I do tend to write them off quickly and not give it a chance and feel relieved when I call it off.

I think him being direct and not playing games is freaking me out. Do I have commitment problems ?