While I was using my MacBook Pro (Retina, 15-inch, Mid 2015) running 10.12.1 Sierra, dark horizontal lines popped up and the screen flickered a little. They turned off and on for a bit and I took 2 pictures while they were on and off. It's been 2 days and it hasn't turned off again. I restarted my computer by it's still there. Is this a hardware issue? What's going wrong here?
Top image has lines, bottom image is normal.