That's weird, there should be a timer top middle of the screen and bullets bottom right. Did you play in full screen mode on a browser, and did you see the target count? Because maybe it doesn't show the timer and bullets when it isn't on full screen (doesn't show the whole game). Otherwise, it's a bug I didn't encounter myself at all when testing. Whichever it is, that sure makes it confusing when you lose all of a sudden.
Yeah, the first level is not that difficult. While I didn't want to show a whole tutorial or explanation, I thought that making the first level too difficult would turn people away or something, and that would not be good.
I think with visible bullets, the 2nd level would be easier to complete already because it would be easier to adjust your aim based on the last shot. In my next FPS project in the future, I'll add visible bullets for sure.