Stress = Cramping?

 Today at work at the nail salon a woman came in to get her nails done. She wanted red glitter French with Christmas lights and a penguin in the form of gel. This started at 12. The client began to become very picky and every once in awhile she'd nod off and her hands would start jerking. I asked her if everything was ok and she said Oh I just keep getting cold chills...... Um okay... So I finally got done with her red glitter gel tips, Christmas lights, and super dressed up detailed penguin and I noticed I began cramping. I worked on that lady for 2 hours. I don't know if my stress started causing me to cramp or if it's just where I was hungry and hadn't peed either.   Have any of you began cramping when you're stressed? I'm 12 weeks and my doc appointmet is tomorrow.