Strong odors during stressful moments

I have noticed several strange symptoms lately that seem to relate to digestion or my bowel movements. The first is a strong, "egg fart" smell that I recognize during stress moments, most notably while driving my car. I do not ever feel that I have passed gas but the intensity of the smell makes me think that it is infact me doing it, especially when other passengers ask who takes responsibility.

When I do fart in a quite literal way (ie, i can feel it), it NEVER smells. Ever.

The latest symptom is a vibration feeling in my bowels that lasts 5-8 seconds and happens anywhere from once an hour to every time I sit down. It feels similar to a car trying to stop with worn brake pads, as funny as that reference may seem after the first paragraph. A definitive vibration feeling that is unique to anything I've ever felt.

I currently take 40mg of Tecta for Gastritis but it does not seem to help the things I mentioned above, if they are in fact related. Any help/suggestions would be appreciated.