Things I liked, This is actually a very fun shooter game you have here! The concept of having a bullet that can only harm enemies in one direction and then you need to reverse it to harm others is awesome and you didn't clutter it by having too many bullets. Only having one bullet allows the player to focus more on whats going on rather than being some sort of bullet hell. I can tell you had a lot of fun thinking of the different ways to use that mechanic!
Things I didn't like, the ability to slash felt sort of useless to me and just like extra garble to give the player. If they are that close to the bullet then they could easily just require it rather than hit it and hope it goes in the right direction. Also in level 7 I believe, the one with the deep pit, the bullet wouldn't go all the across despite fully charging it. Lastly try not to make your builds saved in a rar file. Nothings inherently bad about rar but when it comes to a game jam, and just sending your games out in general, you want to avoid adding extra barriers of entry when you want them to play it.
Overall though I really had a blast playing your game and I hope you continue to work on many more games in the future!
- Von Harley