Hey! So, let me try and answer all of that^^'
1- Yup, sometimes it is a bit weird which is the case because this is the first time I have created where you possess of a bullet, so sometimes it doesn't work fully as intended.
2- That is the entire point of them. Once they hit you, they stay in place and start damaging you. To stop them from doing that, you have to kill them.
3- I personally think that the concept is not bad, I just did not have enough time to think it through enough, so I didn't really do that much with the concept. It was just really difficult to get a good and well thought out idea that makes use of the limitation, but I get that it may make things too hard :/
I personally did not notice that it went too hard, but as a developer, you obviously don't. But thanks for your feedback, I'll try to find a way to make it a bit less hard (even if it's just giving you more HP) and to give the concept a bit more depth! :D