I signed a rental lease before I looked at the apartment but I did not like it, now they're taking me to court?

Me and my friend were looking at apartments and thought we finally found one. My friend went and looked at a model before me and loved it. So the next day we went to go look at the actual. When we were speaking with the Rentor, she had told us to sign the lease before we looked at the actual. I told her, what if I don't like it, I don't want to sign the lease now, she said the lease will be voided after you sign it if you don't like it. So me with no renting experience at all believed her and signed it. We looked at the actual and hated it. It was old, the closet was broken, there were stains on the carpet, it smelt bad, and everything just looked so aged. So my friend hated it and I was ok with it but she did not want to move in. So we left telling her we will decide what to do. After wards My friend called her and said we don't want it. After that we thought it was a done deal and forgot about it. It has been a year later and I received a random note on the door of the aprtment we are staying at now saying my name and my friends name with a phone number. It freaked me out so I called it anonymous asking who it was. It was a man on the phone saying it was a private investigator and that I was being sued. I flipped out and said from who, he told me metropolitan ociates, I had to think real hard for a second because I had o idea who that was. He said it had something to do with rent and wasn't exactly sure about it. After I hung up, I thought about it for awhile and was thinking who is suing me, I thought it was a scam for little bit until he said he would come by and give me the court paper doents. He came by and gave them to my friend. We figured it out after wards and were shocked. The private investigator had also told us that he tried stopping by everyday since December 14th and we never answered are bell. He said for every time we did not answer that there was a 50 dollars charge and we owe him 500 dollars. There were days were my friend stayed home all day and never heard a doorbell ring. We thought everything was crazy. Not only that but I ordered a credit report and it showed that metropolitan had pulled my credit every month. I dont know why put they never had my permission to do this. My court date is this Monday and I need some advice, HELP PLEASE!