It's clear that a lot of effort went into it. I think the time limit is an interesting twist on a genre that can often encourage playing slowly and carefully - but the current implementation is frustrating. I'd recommend replenishing time and respawning oil on death (from any cause), and making the time limit act like any other level hazard. This would make things less frustrating, and would also give the game more room to grow if desired, as the forced restarts would become more problematic if you add more levels.