Most manufacturers probably err on the conservative side on expiry dates, so I wouldn't sweat it too much unless it's way past due. I've used aspirin with an expiry date two years before I took it, and didn't even get a stomach ache. (That was by accident, and I don't suggest it, mind you.)
Although it does suggest that you paid too much for the stuff - they can't be turning their inventory very often, so their markup has to be very high.