How long does cannabis-induced anxiety last?

Hello doctor,

I was diagnosed with severe emotional breakdown four years ago for which I am taking Sizodon. I used to discontinue the medicines often and never completed the complete course. Off late, I again started smoking some cannabis on a regular basis. I got a panic attack while smoking. My head was beating and I could feel pressure on top of my head and around the head. It felt as if some energy was stored in my head. My doctor said it is due to severe stress and anxiety and prescribed Ativan 1 mg along with Sizodon plus. The dosage was tapered off to 0.5 mg after two weeks and was completed after another 15 to 20 days. It still happens that every morning I wake up to some kind of weird feeling around my head. It still feels as if some force is about to go up from my head. Possibly muscle tension. However, yesterday after taking Sizodon for an hour while going to sleep I felt as if I am very high on the medicine the head was shaking continuously and I could feel electric sensations. I have already done a CT scan and no abnormality was found. Is it possible that these feelings are due to Ativan withdrawal symptoms? I have stopped taking Ativan for almost ten days now. I also want to know if any of you have come across a similar case of cannabis-induced anxiety or similar symptoms, how long will it take to get relief from cannabis-induced anxiety? It is exactly two months and this is happening again. I have stopped smoking cannabis, however, I am still smoking around eight to ten cigarettes every day. Kindly help.