Agree with above. As this is your first beer fest--look for the dump bucket.
If you get a bad tasting beer or one that isn't to your liking--dump it and move on.
I always struggle with doing that as I don't want to be rude and it goes against my midwestern upbringing (cue mental image of Mom saying "Clean your plate, young man! There's starving kids in (insert country here). 'Waste not, want not'.")
But, it is OK to do this. Dump buckets are the norm at BJCP competitions,the GABF, and most beer fests.
Save your taste buds and your tummy space for the good stuff!