Could it be wheat?

Yesterday I decided to quit wheat for a week, to see if there may be a noticeable difference in pain. Unfortunately, I woke yesterday with greater-than-usual pain and actually took one tylenol-codeine tablet, something I rarely do. I didn't notice any effect from it, although the pain did gradually lessen yesterday and it isn't so bad today. I'm going to try to stay off any pain meds for this week. We shall see.