Assignment extension?

I emailed my one professor last week and asked him if it would be possible to get an extension on our big final project that is due May 1st and he hasn't gotten back to me yet. I am incredibly frustrated by it but it's pretty typical of the professors in my program - teaching seems to be the lowest thing on most of their priority lists. Seriously, I had only a handful of professors in three years of grad school who seemed to enjoy teaching and who seemed to want their students to learn. Those that teach via distance format seem to be by far the worst. So, I'm not sure if my professor is ignoring me or somehow didn't get the email or what? He did respond to another student's question in the meantime so I know he's been online to see it. I guess I have to email him again and risk being a nuisance.