Should I contact him again?

Ok - I went out with a guy on Thursday night and we had a great time. He brought up going out again and I said I was interested. We talked about calling each other. I texted him late Friday afternoon to say I had a great time and thanks again. He agreed and said he was glad to finally meet me. We went back and forth a few times and then . . nothing . . I haven't heard from him. My friends say not to contact him again, but is there anything wrong with just saying hi again a few days later?