From what I can see, you may have just overfed a little, White Widow seems to be very sensitive to nutrients (I have to go less than 1/4 str to not burn it in hydro, 1/4 is about right for soil). It also tends to be a very very slow grower during veg (having to veg for a very long time under a HID to get it reasonably big, probably longer with CFLs/LEDs), and are usually pretty compact & small, carrying it's Indica traits there. The downside of the plant is that it doesn't grow very big (If you want higher yields), but with how much THC is produced by that plant, it definitely makes up for it with that. The strain can take about ~60 days + the first initial 1-2 week period of when the plant is switching to flower, but to really pack on crystals, you can try going 9-10 weeks.
Other than that, it looks like you're doing well, what brand nutrients are you using? I highly suggest for soil, using the earth juice line (Veg, Flower, Catalyst, Microblast & you can get them in quart size), and throwing some molasses in your nutrient/water mix for the last few weeks of flower. Definitely go light on nutrients for this strain if you notice burn.
When I did one WW plant in soil this last crop, I vegged for a good month, and it still didn't get much bigger than maybe 16" if not less, and was only topped once, whereas my Mango & Pineapple express, given 2 weeks veg, are MONSTERS. Only got about 26 grams off of the WW plant, but boy does it look tasty.
