Which pill combination could've caused my nausea?

This morning, about 10 minutes before I ate, I took the following pills:

- 2 metamucil fiber capsules (I’ve been taking these for a month because I have IBS; I take 6 per day as the bottle suggests; never had any side effects)
– 2 midols (I was feeling bloated; I’ve taken these before with no side effects)
– 2 gas-x pills (again, for the IBS; my bloating is uncomfortable, so I use these in conjunction with the midol for gas/water retention; never had any side effects)
– 1 AZO yeast (I’m prone to infections; just started taking this; took it last night alone with no symptoms)

Well about 10 minutes after taking these, right before I forced myself to eat breakfast, I got a wave of nausea. It stayed with me for about 3 hours, then faded a bit, but I still had no appetite. I thought maybe it was from dehydration, so I drank 2 bottles of water over the period of 2 hours. A couple hours after that, I still feel nauseous but it’s not as severe. Still no appetite though, and getting close to dinner time.

Was it most likely the combination of pills or just the AZO? I don’t want to have to go through school and work again feeling nauseous all day. I checked the reviews for AZO and found nothing about nausea. Maybe I got a touch of a stomach bug or something, but I felt fine before taking the pills.

Any ideas?