Employment Law Information

Recently I went for the interview to the restaurant, it went good but the manager asked me how old I am. I told him because I needed a job and didn’t want to be rude. But i think it was illegal. Then he asked me if i can come for the working interview. I asked what is it. he said it is when you come to work for couple hours, we dint pay you, we basically look at how you perform. I said ok and came to work that day. The couple hours turned into 5 hours. at about 9 pm there was basically nothing to do, almost all the people left. he didn’t ask me to go home, cause I’m done with the training. Instead i was sweeping the floors and cleaning(not sure if it was the part of the training too)) He didn’t tell me what to do, in fact he forgot about me. Well, I didn’t like that attitude. But of course i didn’t say anything and was nice and smiley. Finally one girl said that i probably do not need to train how to clean the restaurant and asked the manager if i can go. he said yes, i asked what is next. He told me to call him the next day. I called him, he asked if i can come the next day for training. i said yes. so i came in and the story repeated. again no attention from the manager and i had to work for like 5 hours. that day i cleaned again. when I asked him what i should do next he said call me. ok i called him the following day. he asked if i can come for the training again. I asked Training? he said Yeah may be you can earn some tips today. Wow… well i went in for the unpaid training that day as well, it was my third day. When i entered the restaurant i said hi to him he said hi too. and didn’t tell me what I’m supposed to do. how long my training is. nothing. So an hour later i noticed that he left. I earned that day 10 bucks cause i had to split with the girl and i didn’t take many tables cause I’m new. So i was pissed by the en of the day. he didn’t say what I’m supposed to do, no guidelines no normal training. he just left. so i called the place later that week. he said Oh hi, i think i dint have anything for you today. I will give you a call later on that afternoon. i said ok, and i didn’t hear from him at all. so now i feel that i had been used. i worked for free for that man for 3 days. he ignored me most of the time. and i must say i didn’t mess anything up, i was a good worker, in fact one table even left the note on how they liked my service. I am from the other country, so i don’t know the laws. But it seems to me that in USA you are not even allowed to be in the restaurant behind the counter without being hired. what if i break the leg on the floor in the kitchen for example? how he’s gonna be liable? I don’t know what this man’s tactics was may be he does it with every new server, so he has the labor for free. So i wonder what my legal rights are? can i do anything about this situation or is it legal?