Thanks for all the additional details.
The symptoms that you have are basically panic attacks. However, it would be wise to get an EKG and Echocardiography done. If these reports are normal (mostly they will be) then you will be reassured and there will be nothing much to worry. This is a disorder of anxiety and occurs because of imbalance of certain neurotransmitters in the brain, especially serotonin, noradrenaline, and dopamine to some extent. Cannabis is not considered a good option for this illness. Medicines are the best options to take care of these symptoms. Paroxetine is the the most popular medicine and my drug of choice. I generally prescribe my patients 12.5 mg per day at night which takes care of their anxiety symptoms. Also certain medicines like propranolol and clonazepam can be given as required when there is a panic episode or a situation where a panic attack can occur.
Also there is an option of cognitive behavioural therapy (CBT). This therapy is provided either by a psychologist or a psychiatrist, in which the therapist identifies impaired cognitions (thoughts) and tries to correct them. They are 15-20 min weekly sessions and there should be around 8-10 sessions to help you with your illness.
Hope this was helpful.
If you have any further query, do let me know.