I've had similar problems recently but randomly, not sure if it me or difference in the pool chemical levels. One day I was sneezing ever 15-20mins in the end I snorted fresh water and that seemed to clear it. Now if my nose feels a bit tickley after a swim I flush it out in the showers with fresh water and don't seem to have any problems now. Might be worth a go, free and no chemicals/drugs.
I found and I know a number of other have that Fink is very short on bike miles particularly if you don't have a history in cycling. If you have years of century rides behind you and you need to concentrate on the run or swim I'm sure it's fine
The swim sessions are ok, I found them a bit hard to complete in 1hr and I managed the swim at Challenge Henley in 1:28 (not fast but not dead slow either). Nice to have a plan when you get in the pool and helps to reduce boredom.
Good book to keep dipping into as is "Going Long".