Jady's got it right. When you're doing two point perspective those two vanishing points are always on the same horizon line. And for that you don't really need to worry about the vertical stuff, they'll almost always be perfectly straight.
When they're not that'll be during 3 point perspective when you want something to look big and menacing. Two points will still remain on the horizon line but the third will be WAAAAAY up in the sky.
Also the thing with photos (and I should have mentioned this before) is that depending on the cameras you're using there will be a certain amount of distortion. I noticed this with iphone photos whenever I'd try to take reference pictures for myself. There may be a slight bulge in the center that will throw you off. I dunno if that happened here but I know it happens to me a lot. x'D
Hope this helped >3<