I suffer from anxiety and depersonalisation, My anxiety in particular has gotten worse over the past few weeks due to getting a new job. This morning I woke up feeling odd like I was in a dream. I turned to one side and all of a sudden my heart started pounding. I got that feeling that I was going to have a panic attack. I fought it (fight or flight) and I feel a lot better at the moment. I’m just worried why when I wake I’m having these thoughts and feelings. Is it normal afterwords to have a pounding headache. I’m also pretty terrified to go back to sleep but need to as I have work in the morning. 
Sorry for my English if it’s wrong I’m deadset half asleep writing.