If you wear your wedding rings backward does this mean you're widowed?

In Western culture this means nothing with the exception the person may not have paid attention when putting on the rings. If the rings are under the finger then it just means the rings are too loose on the person's finger and has slid under their finger.

If you wear a simple gold ring then you cannot wear it backwards, whether there are inscriptions on the inner side of the ring or not. It is just as difficult to say you are wearing a ring backwards if there are jewels set in it. This type of ring can be worn on the palm side of the hand, but this is not backwards,

Widowed persons may wear their ring on the right hand to signify that they are widowed.