Can someone tell me about my blood pressure reading?

I took a blood pressure reading on a machine at work and it ran 120/92 with a pulse rate of 88. Now I was working before this, but according to the machine its supposed to be in the 80ish area. I
m a 19 year old female and I am a very bad hypochondriac. I've been eating mostly fruits/veggies some seafood. I stay away from fried foods. I only drink water. I don't really exercise much, but at work I am required to lift heavy boxes and move around a lot. I've also started to notice sometimes I have this pressure in the middle of my chest. I'm kinda scared its a heart attack waiting to happen.