As the comments to the questions state, this is a question on the research state about the generation of the universe, and the first moment is modeled in the Big Bang model. The real beginning point is not yet known even in this model since gravity has not been consistently quantized within the model, only effective theory is used. Nevertheless existing theories incorporated in the Big Bang can answer your speculations.

I have some theories about what form of energy it could take. Maybe all the energy was chemical energy, waiting to release energy when the atoms interact.

Not possible: Chemical energy is of the order of electron volts, and electromagnetic in form. The energy of the universe at the first 10^-32 seconds you can see the scale of energy versus time here:

Or is it an osmosis-like energy? Where the matter wants to move into the lower concentration of space from it's super high concentration (Is this even a type of energy, if of I would like to know what it's called).

There does not exists such a classification

Or maybe was all the energy in the form of matter, later being released in a nuclear reaction.

Energy in the BB model is not in the form of masses at that time point, it is four vectors of virtual particles which carry varying energy and momentum, off mass shell as far as matter/mass is concerned.

As the comments to the questions state, this is a question on the research state about the generation of the universe, and the first moment is modeled in the Big Bang model. The real beginning point is not yet known even in this model since gravity has not been consistently quantized within the model, only effective theory is used. Nevertheless existing theories incorporated in the Big Bang can answer your speculations.

I have some theories about what form of energy it could take. Maybe all the energy was chemical energy, waiting to release energy when the atoms interact.

Not possible: Chemical energy is of the order of electron volts, and electromagnetic in form. The energy of the universe at the first 10^-32 seconds you can see the scale of energy versus time here:

Or is it an osmosis-like energy? Where the matter wants to move into the lower concentration of space from it's super high concentration (Is this even a type of energy, if of I would like to know what it's called).

There does not exists such a classification

Or maybe was all the energy in the form of matter, later being released in a nuclear reaction.

Energy in the BB model is not in the form of masses at that time point, it is four vectors of virtual particles which carry varying energy and momentum, off mass shell as far as matter/mass is concerned.