House sparrow being released?

Hello! Today morning I released a young sparrow, and now I have doubts what I did was right. I hand feed him 19 days (when I got him he was around 3-4 days old), he began to fly one week ago, on Tuesday 21. For the last days I hand reared him every 2 hours, but he also fed on his own... he didn't start to eat big seeds yet. Last three days he was very noisy, and I didn't want him to be closed in an apartment or get used to humans, I also thought he was good in flying. But now that I think back, I truly hope he could find food and other sparrows, and wouldn't miss the syringe. Do you think I should let him go when he would be older and would eat on his own all day long, on your experiences? a also red on the net that sparrows get independent 7- 10 days after they leave the nest (but they leave the nest when they do not yet fly). He also wasn't used of the weather outside, do you think he could find a shelter? And I have one question more..why do you think he was so loud? Even when I fed him he didn't stop cheeping. And I really doubt he was hungry. Thank you very much for your answers! Jasmina