I dont think that you screwed up on anything.
Just wait for his call or email. If really dun have (when he suppose to call), try to contact him back. But for now, sit back, relax and enjoy your free time at home...hehe!

Response +ve at 1st? This always happens. Even when i had my 1st interview, i was the only one can answer the questions, was having high hopes, then end of the day, failed!
So, i will advise you to take it easy on this disappointment. One failure doesnt mean you will fail again. And think that they dont deserve you, not you dont deserve them.
Try to look for other company. If the company want to forward your resume to other department, be it. Who knows you might be lucky nxt time.
Cheers