While waiting for Ms Knot, measure out your sit bones. Then measure the sitting portion of your saddle.

Classic symptom of too narrow is when you get off the bike after riding, you feel like your nether regions need to fall back into position. For me, it was that the tailbone area hurt like the dickens after I'd get off the bike. Riding wasn't that big of an issue, but stopping....ooooh, that hurt for a good 5 minutes.

Besides a wider Brooks, wide, yet not quite too much padding, saddles are Topeak's Allay and Selle SMP Lady Strike. Specialized also has a 175mm saddle but it is a bit poofy.