Other forces of nature?

Factual Questions
1

Does our current understanding of physics allow for any other forces of nature, or is it somehow restrictive to that possibility? More specifically, could the questions that Dark Matter hopes to solve be accounted for by a previously unknown force, or perhaps multiple forces?

I know this sounds silly but I was imagining life at the quark level and figured that my quark-sized self would live in a world where the strong force would be like my electromagnetism, which in turn would be like my gravity (I realize that it’s not anywhere near that simple but bear with me). Now if I took my quark telescope and started peering out into the universe and thus discovered planets and stars. I would soon find that there’s no way EM could account for stars and planets to behave in such a manner. But since I don’t really feel the effects of gravity at this scale, I am unaware of it and so unable to determine the behavior of the planets.

Could something similar to this be happening to us?

2

No real reason there can’t be more than four fundamental forces; in fact, the search continues:

3

Dark energy, AKA the cosmological constant, is sometimes referred to as a “fifth force”, and popular accounts sometimes refer to it as a repulsive counterpart to gravity. The current paradigm for describing it, though, has it as a perfectly ordinary manifestation of gravity, as produced by a very peculiar sort of material.