Need your advice on an issue PLEASE HELP!?

Ok so im a woman and best friends with a man.we met in work and became so close told each-other everything he was almost like a brother to me!.He is a single father of two children.We went on a date last weekend with his children it was really fun and then afterwards he got a babysitter and brought me out to a restaurant which surprised me as i thought the date finished when we were done with the kids .which was very thoughtful :) but it was in the restaurant he actually began act strange like kinda panicky? then when we were on our way out before we got to the car he began bursting out feelings and told me before he liked me but now he loves me for over a year now and that i never noticed his feelings and he wanted a relationship but was afraid of me saying no and cares about me and so on . and i didn't know what to say he wasn't drunk either i was gobsmacked didn't say anything so all i did was kiss then he dropped me home and i thanked him and bblah bla blah! NOW he has been avoiding me and hasn't called because i think he thinks i rejected him i also think i gave him the wrong impression that i didn't like him i just never said anything as i never knew he was ever interested i really like him too .i know he hasn't dated in years or had a relationship and has always done the best for his kids.there mother isn't in there lives at all.This guy i know him with over 6 years hes the best friend you could ever have and his kids are so friendly and so well brought up i think i ruined it.what do i do i havent heard from him since saturday night?Also is it a good thing to get in a relationship with a close friend i dont want to feel im invading his childrens space either? Thanks for any help :)