I'm not a doctor.
When they do a spirometry test, they're looking for a change of >= 10% in your FEV1 after you use an inhaler. In your case, the change was only 1.82% from your initial (pre-inhaler) FEV1. Also, they look at the flow-loop that's generated from the test, to see if there was any obstruction that was reversed after you use the inhaler. The normal range of FEV1 is 80-120% predicted. You're within that range.
I'm assuming you use medicine for your asthma, since you indicated you're an asthma patient. I don't know the rules for becoming a fire-fighter if you have asthma. I know for the military you have to have a normal spirometry test after being completely off medication (not even a rescue inhaler) for a year. From the bit that I know, it looks like your spirometry test was normal.
I hope you achieve your dreams of becoming a fire-figher!!
Just a note: I don't know if the FEF 25-75% also has to be >= 80%. Perhaps someone else in the community knows.
Again, good luck.