DISCLAIMER: i am no expert and i dont use marketing.
In my experience, It is hard to sell games. Don't be put off if you don't get sales.
Putting items here on sale will help IMO. it increases views and your game will get picked up by deal sites.
Looking forward, Just keep making things, and look toward making a bundle (alone or with others).
If you want to increase your chances of sales perhaps make an android version too.
You game looks cool, if it takes time to get a couple of sales it does not mean its a failure.
I have posted plenty apps that have made <$5 a month. But like to take the knowledge gained and just press on.
Eventually you will find some success. maybe where you least expect it.
respect for making the game and taking it seriously.
The look of your game reminds me of Amiga Public Domain games and its really nice. It would definitely appeal to older gamers.