K2 or spice contain synthetic cannabis (marijuana) in potent form. I would like you to know that cannabis is well-known to cause both anxiety
. Anxiety is often accompanied with symptoms like irregular heart beat, breathlessness, sweating, chest pain
, tremors etc. At the same time, alcohol also is associated with anxiety disorders, and less commonly with paranoid symptoms. Hence in your case, both cannabis and alcohol might have contributed to your problem. I would advise you to completely abstain from cannabis and to cut down alcohol intake significantly. If you still feel unwell after that and your tests continue to remain normal, please consult a psychiatrist
so that a proper assessment can be made and medications started, if deemed necessary.
Hope this has been of help. Best wishes.