Yes it does, good point actually haha, I changed it to bullet speed from multiple bullets because it made the game too easy, but didn't think to change the Shop button's text. I'll change it to 'Upgrade Bullet Speed' instead on next update, thanks for feedback.
Thanks for playing I'm glad you like it. Yes getting to wave 11 is difficult, need some skills for that haha. I play tested it loads of times and only managed to get half way through wave 12 once. Also thanks for the helpful bug spotting, I've been looking into what you said and noticed that the ammo wasn't set to update on the UI when collected, but updating when pressing fire, so that's why it appears as if it's only giving you 5 ammo, but that was an easy fix. The Suit Zombie HP was not set up correctly either but that will take more time than I have tonight to finish that off properly, so will update with fixes once it's ready.