My question involves criminal law for the state of: California

Two days ago, I went to a retail store and brought a pair of shoes. Before leaving the store, I put another pair of shoes(worth $20.00) into my shopping bag without paying it. By the entrance of the retail store, I was caught by a undercover police (which I thought because he showed me a badge) and a police officer. They took me up stair to a room with two other people (which I believed they were the worker of the store) and one another police officer (while they taking me to the room, the undercover police office ask me did I know why I got caught and I said yes). They asked me to show them my purse. Then they search my whole purse include my wallet and my cosmetic bag. They asked me to give them my ID and also asked me to write down my name, address, date of birth, social security number, and my phone number in a note book.

After this, they asked me to sign three papers with same notice, which is about they will send me a bill in between $50 to $500 within the next 30 days (I think they were same, but I could not remember because my brain was blank for that whole time). After I signed that three papers, they gave me a notice which is call "Civil Demand Customer Notice". They also wrote down my information in another form, which look like a government form (because it seems with a kind of government logo and with a white copy on top and a pink copy on the bottom). But they did not have me to sign that form. With this whole process, the police officer was with me. After this, they told me that I could not go to that store any more within California. Then they let me go.

This is my first shoplifting and I am sure it will be the last. For now, I am so regret for what I did and also so nervous about this. Do I need to go to court because I was caught by two police officers? Will I go to jail? Should I call for a lawyer now? If I need to go to court, do I need to guilty because I already said I knew why I were caught? Will I have record for this? If yes, can the record be erase? Will my employer know what I did?

I had under a lot of pressure since I went to college. Started by that time, I had been always thinking that I want to take stuff from store but did not put it in action until two days ago. I don't know if this is a mental problem or not. I am super scared now even thinking to kill myself. Could anyone tell me what to do now? Please.