A good submission, visually appealing and with a nice soundtrack as well. Effort has clearly been made to the polish and user experience with the game. Clearly meets the requirements as defined in the brief, so well done with that.
The main issue is difficulty, the hitboxes on the objects feel a bit too large and/or there are too many spikes spawning at once. It would be nice if it started off easy and then the higher your score the more difficult it became, meaning that it would exponentially get harder as you played leading to a clear skill progression. Currently it is difficult throughout so less experienced players will struggle to remain engaged, bear in mind who your target audience is. In addition, consider the way players can download or access your game, is it the best way you could have done it or are there alternatives that you could have done.
There is a solid concept here, and with some tweaks to gameplay and improvements to graphics & user experience, there is a game there that could be put on some form of marketplace. Great work.