Im experiencing: nightmares and insomnia, high pain tolerance that is not of other medical nature, spacing out, feeling far from self, people or reality, fragmented memory, self harm, numbness & emptiness, mood swings, cant relax, easy triggered?

It is not feasible to provide a meaningful opinion without taking additional history, physical examination and may be some tests. It would be prudent to see your doctor and discuss if you may be depressed. Counter-intuitive as it may seem, exercise may help. Start with low intensity exercise such as walking and gradually increase the intensity as tolerated. Drink more water. Wish you good health!

You detail a number of psychological changes, and these several issues would require a thorough psychiatric evaluation. It is not feasible to currently pinpoint a diagnosis, but an expert can help with both a diagnosis and therapeutic interventions to control and reverse your issues. Do not let this go, as relief can be within reach.