All the 'Intro to Quilting' tutorials online seem to leave out a fairly vital detail - when do I wash this thing?

I've not bothered washing tied quilts before gifting them but I'm doing my first machine quilted lap quilt out of a jelly roll. So I figured I should wash it and get the shrinkage over now? That was my thought and I've gone ahead and washed the front and back and ironed.

I think this was correct, especially since I lost about 2 inches in one direction from the front.

Thoughts?