Does every story need antagonist?
Question: If I have a problem to solve and the hero has already enough obstacles, do I still need a bad guy?Answer:
Not every antagonist is human. Sometimes Nature can be the antagonist. Society, a supernatural force, an animal, or a machine can be the antagonist.
Even a human antagonist doesn't have to be an evil person. He or she could oppose the protagonist with all the best intentions, or simply have a different agenda that is incompatible with the protagonist's aim. Sometimes too, different characters can take on the role of antagonist at different points in a novel.
All that matters is you have an entity that opposes or seeks to prevent the Story Goal from being achieved.
My guess is that your antagonist is somewhere in that list of obstacles you've created. But you'll know if you need an additional antagonist if the story goal will seem too easily achieved.
Without an adequate antagonist, there's often little to stop the goal being achieved in the first chapter. Or the goal may seem so easy that the hero's success is no big deal.
Readers enjoy stories about characters who must face tough problems, and antagonists are there to make the problem tough.
So, no, you don't need a comic-book style villain to be the antagonist. A guy in a black cape and long moustache hatching evil plans would be out of place in many novels.
You just need to make sure the protagonist has a big enough problem to tackle.