We met about 3 months ago and it got serious very fast. He met my mom and sisters within a month and he took me to his daughters wedding and I met his family and friends. I was introduced as his girlfriend to everyone. Then a week later he said we need to slow down, he isn't sure if he is ready for a serious relationship. He said "we need to slow down, I think". What does this mean?

He text almost everyday and he calls me on the phone a couple of times a week. I don't know what to think. He is coming next week to my daughter's school play and then 2 weeks after that, he is coming to my graduation. He told me last night that he misses me.

I don't know what to think...