I personally can't do tea. Although there is one called sleepy time, I did the best with and had that at night before bed, it can help you sleep.
Coffee I do drink in moderation. Sometimes it even helps, sometimes if I over do it it doesn't, but I am an alternator anyway. Mainly I have to watch it doesn't cause me any pain. I gave it up for quite a while then when back to about a cup, maybe two, depending on the day.
"high caffeine intake and soda probably wasn't good for my gut"
Probably not. The soda can also increased bloating. Everyone with IBS should cut out the soda. Maybe an occasional ginger ale. Ginger can help nausea and sometimes calm the gut, but I don't recommend a lot for sure. Its mainly the carbonation and massive sugar.
broccoli is really good for you, but it can cause gas. Only eat a little at a time.
"Long story short, maybe having had high BP readings will be a blessing in disguise."
I know what you mean there. Time for some changes. Salt can also increase bloating and water retension. Most of the things for high blood pressure can be benefical for IBS as well as hopefully preventing a heart attack. ;)
I know I have some work cut out for me on this as well. I smoke, so that has got to go.
Let me know how you feeling as you progress.