I agree with what @jb111 said about your cover, OP.
Also, the following:
(1) It doesn't matter how good your book, writing, story, craft, or anything is if you can't get visibility. The only way to get visibility is to advertise. Just putting a book up on Amazon isn't helpful, and after the first 30 days, any new-book visibility you might've had is gone. Try different ads, spend just a little, see if you get any traction. Do not overspend.
(2) I gather that this is the first book in a series. It'd probably be better if you waited until at least book 2 is published before you start spending much on book 1.
(3) You have to decide for yourself how you want to approach your writing career. Are you doing this to make money? If so, you have to stick with the market, write those tropes into the ground, and forget about what it is you really want to write/say/do. No amount of editing or cover design or ad budget can make a book a success if it's not what the market wants. On the flip side of that, really poorly written books can be huge successes if they hit the market in the right spots. Don't believe me? Open up the Look Inside on top-selling indie books in several genres. Good to-market storytelling is far more important than "good" writing. Readers don't care. They want a story they enjoy.
(4) Pricing. Indie authors have destroyed the pricing of ebooks so that even $3.99 seems "expensive" for a 100K-word Kindle edition by a little-known author. I don't know what to tell you about this except that pricing your book above $3.99 is probably pointless. Do you want nonexistent royalties? Or do you want people to buy your book and make practically nothing from each sale? Hey, even at $0.99 with the 35% royalty, if you sell 2,000 books, you've made $700.
(4) Whatever you do, do not ever give up. Keep writing. You'll figure it out as you go along.