This is a fine game , but you should have made the ants move faster or added a new type of ant that is faster but has lower health.
The game feels a bit unbalanced because I was getting more bullets than I needed and I never felt that I have to keep on eye on how many I have left. Also, the health seamed a bit unnecessary because you can easily avoid the ant and never get damage.
Another thing , you could have made it so that when a generator gets destroyed something happens that changes the gameplay a bit to make it more intense.
Another two small things: I can't shoot an enemy through a health pack and the enemies look like they are floating above the ground (a bit , not much).
Overall the experience was ok and with a little bit of tweaking it could be much more enjoyable.