It's probably that you are suffering from stress. Stress leads to hormonal and neurotransmitter changes which cause variety of symptoms some of which you are feeling for past few days.
So try to lessen your Stress, eat a healthy diet, do not take tea or coffee after 6 pm, do not take any addicting substance.
Do some exercises in morning and try to relax in evening and do not think about sleep.
Next Steps
If still you are not getting relief then kindly take some professional help.