Hello and welcome!
You need to call your doctor and get your meds back on track. Many docs will not Rx even a refill without seeing you first, which is why it is very important to keep ALL of your appointments. How did you run out? Did your doctor not give you refills?
Also, be very careful trying to substitute another medication (Ativan) for the one you are supposed to take. That is a job for your doc. Ativan and Klonopin, while both benzos, are very different in their half lives and duration. Plus there isn't a gold standard in equivalent doses.
Please call your doctor first thing in the morning to get this straightened out. This isn't something you should be doing on your own.
Let us know how you're doing!!
Aaawww.... I had the same thing happen awhile ago, and I know just exactly how crappy that is. You can try Valerian Root, available in herbal remedy sections of most large stores. It is not the same as your usual med, but may take the edge off a bit. I found that it made me feel a bit 'high' and would give me a headache as it wore off. I suggest you try this at home before attempting any outside activities on it, so you know how it affects you in a safe environment. Do not take more than the recommended dosage. Otherwise, practice your breathing excersizes, and calming techniques as often as possible. And get back on your regular meds ASAP! - Blu