sweet game
It was a great game. Good controls, no glitches, simple and intutive.
Just a couple suggestions
1. get rid of those amoebas that are colored exactly like the blood all over the ground.
2. you should make the running speed able to be upgraded more than once
3. maybe an upgrade for accuracy at longer distances? (decrease the spread, like the guy before me said)
4. be able to sell/throw away guns so you don't have to scroll through so many to find the one you want