As you said the tutorial is a little hard to figure out lol. And sometimes when I shoot, the virus seems don't get the damage. And I think it might be intended that your bullet pill will be blocked by other pills, but it was a little confusing at first why the shoot does not shoot anything out.
I hope when hit happens, there will be some feedback like sound or animation or just a flash.
The shortcut on the top right corner is confusing. I tap one and it sends me back to the menu lol.