Well, any progress is good, even if a little: +1
"I think one of the main issues I have is that I can over estimate what I can do in an amount of time. I though 10 days to do the main coding, 20 days for 10 levels. It took from the top of my head 12-14 days for the main coding and 16-18 days for 4 levels."
Oh, god, I've been making games for 8 years now and I have this problem all the time. The only advice I could is: Double the expected time and pray to lords of chaos that it'll be enough.