Yes the same thing happened to me.
One item was priced 250% higher one month later (but if I used a DIFFERENT computer they didn't recognize, the online prices matched those in store). ALL my items that I had ordered listed repeat-order prices that were 15% to 250% higher!
This IS price gouging because they are charging different prices to different people, discriminating AGAINST THEIR REPEAT (read "loyal") CUSTOMERS. Not only that but if you order online, now, and pickup in store you will be paying those higher prices too.
This brought them a stock jump recently.
Watch your prices! Try clearing all Walmart "cookies" if you know how, and COMPLAIN.