I'm happy you liked it! I wasn't planning on playing for so long, but what could I do? You made a good game! :D Cool that I discovered something new :)
I think it's good that you can't shoot backwards. That's a limitation that sparks your creativity, even though it can also be frustrating.
I think if the bullets bar was more like a list than a bar it would be much more intuitive, because I thought it was the shield (since the shield is also white) at first. If it looked like the bullets I would have probably understood it sooner.