No level save and level 2 impossible?

[tzetsienghwaang]

I finished the first level and got told level 2's monsters are so strong my shots won't damage them. Sure enough, the monsters all got past my towers even though I tried all towers I could afford on them.

After losing, I found out that I had to start all the way from level one again. Is there no level save and no help on how to defeat a single monster? If not then this is truly frustrating and I don't think I want to play it again from level one.