Suggest Treatment For Panic Attacks

Have had panic attacks in the past 12 years (2002 upon reaching menopause) while driving on the Garden State Parkway (GSP) in NJ. Took Lorazapam to get me through driving short distances on the GSP (up to 25 miles - I used to drive up & down the GSP for 60 miles with no problems for the first 41 years of my life). Don t know how, but I was able to drive on the GSP without Lorazapam for quite a few years (2005 - 2008) and then it returned again so I had to use Lorazapam to drive on the GSP again. That worked okay because I didn t drive on the GSP that much. Then all of a sudden on the Sunday before Memorial Day 2014 trying to drive to the beach (20 miles away) on route 9 (no where near the GSP), my right driving leg started shaking uncontrollably 1/2 mile from my house. I made it about 2 miles when the leg shaking caused a full blown panic attack & I turned around & went home. The next day & for 2 to 3 days per week during the summer, I took 1 MG Lorazapam to get to the beach & back. However, in the past few weeks, even driving 3/4 mile to the Shop Rite has made my leg shake like crazy & I ve started taking 1/2 MG lorazapam. Then I couldn t make it to the beach on Labor day with Lorazpam. I m feeling so desparate & housebound now. I m only 60 I retired at the age of 59. Could my leg shaking while driving be a physical problem or is it still part of a new panic attack symptom. I have my semi-annual appt. with my GP on Monday, but I m not sure I ll be able to drive there. The old panic attack feelings of heart palpations, don t really return. But I just know I can t drive with my leg shacking so much, so I return home before that other panic symptoms set in. What should I do.