I am not sure if you may be having what I had for a long time - Nocturnal Panic Attacks - I kept waking up trembling and also gasping for breath at times when it got really bad. This was about 20 years ago, and they prescribed Diazepam - to treat what was known back then as "Night Terrors". Thankfully, it put an end to this anxiety problem.
Also, Sleep Apnea may play a role, in the last 6 years, I started to have similar problems - waking up in a very nervous and shaky state, but it nothing close to the "Nocturnal Panic Attacks" of my youth, but it was still high anxiety and shaking - my doctor recommend that I get a sleep study done, and sure enough, I was diagnosed with Severe Sleep Apnea and followed the doctor's orders.
Since then, I had wonderful sleep and feel so much more rested...
Just a thought - if it continues to for over a month - I would definitely make an appointment with your doctor.
Hope you feel better