Brake Loud Noise problems of the 2013 Cadillac ATS

I have had 4 recalls on my Ats since purchase June 2013. Starting 2/5/14 with only 3308mi taken the car in several times for squeaking sound when backing out of my garage complained after fourth visit with the same complaint and listening to the dealer to say that was normal final on 5th visit on 12/10/14 7960mi final solve the problem. Several complaints about when back windows are roll down there is a loud squealing sound that hurts your ear and distract your driving again I was told that was normal how can that be normal when you can't roll back window down for fresh air. All so complained about losing radio signal on several occasions penske reprogramed. Replaced weather strip around front doors driver& pass side 8/20/14 6521mi. Several complaints about how rough the engine runs when stop at red light on 12/10/14 reprogramed engine. Is there any safety station I can take my car for safety check. I am afraid to even drive this car on the freeway at high speed. I paid over $37,000 the car has been in the shop more than the previous car I was driving which was 2001 Buick lesabre. I don't feel that penske Cadillac is being honest with problem I was told that the loud noise from driving is coming from exhaust system. Please advise on where I can go to get a second opinion without voiding my warrantee. What is the lemon law regarding these issues? I really don't feel that I brought a new car by all the trouble this car is giving me. Back and forth for repairs.