GAWD! Your employer HAS to tell you to go take a break/lunch? 
YUP Gina, in the hands on workers everyone waits until the whistle blows to take a break. One can not just decide to walk off the job when they want a break.
Most States have to give workers a 15 minute break every 4 hours. 30 minute break for lunch is not paid for. A 8 1/2 hour in location.
Worked at a plant that had just 7 1/2 hour work days, that means in that time one got just that one 15 minute break.
Union job, and the 3rd. shift was a bitch. Start work at 11:30 pm-----3:30 AM 15 minute break and headed home at around 6:00 AM headed out the door.---Mind you the jobs even with a Union did not have any kind of stools to sit on so it was stand up jobs on bare concrete and come to find out most of the workers were on work realise from the Jails.--Worse job I ever had, water on the floors with electrical wires on top, no one would tell me who my Union Rep. was and the only job I ever quit after less then a month.
No wonder I despise Unions for the workers that toil in today's world. In order to work I had to join 2 unions that had to be in cahoots with the company's as conditions were awful.
I worked at perhaps 3 company's of the nonunion sort and received better working conditions, better management and a sense of loyalty to the Company's. I came into work to help keep the Company alive and vibrant, not to get but a pay check for just showing up with any protection of my job, it was all up to me.
When one gets out into the world of Mule work and finds satisfaction in being able to handle it and know ones is valuable not for anything but their work, no connections to anyone, no Union and a fire at will from the Company, one learns to respect what ever ability's they have, take pride in their jobs be it sweeping floors to 100 pound woman lifting 50 pound boxes.
This is the reason that the Mules often make more money then then the trained office staff, OVERTIME and a damn I can do this.-------No Union back up, no laws that say a slacker has to be paid the same as a hard worker.
Have to get out there and get your hands dirty, work your ass off, and 22 years from now have the satisfaction that you gave your all, forged ahead with no back up, you did it all by your self.