Thanks for playing! Hmm that sounds like it's an issue with the mouse not being captured properly. If you head into fullscreen immediately and stay in full screen during play, I think that won't happen. I'll be sure to check your game out next :)
Hello, I must have been tired yesterday, the aiming was perfect in my games today, well done! I would advise you then, in the settings on itch.io to force full screen mode in this case!