I think i messed up

I have been talking to a co-worker since the end of last year, and had gone out with him a few times after work. Everything was pretty good honestly, but he recently came to me and asked if we could date. I was kinda thrown off by it an didn't give a straightforward answer, and now i have no idea if I should just leave it alone and wait for him, or if I should clarify something. Is it simple enough to text or should I wait to see him in person? Kinda wish I had just been upfront, but I was just nervous. :/