I was not expecting that!

Today I was at the allergist's office, trying to qualify as a participant in a research study. One of the qualifications in my pre-screening appt was getting at least 80% on the Spirometry or lung function test. I just wasn't getting it last week when I tried. Even after all the meds I have been on this week, trying to improve my lung function, it just wasn't working for me. The way they were doing the test was also slightly different than the way I'm used to doing it. I was initially told that I did not qualify, they didn't want to put me through the whole day thing when I came back if I couldn't reach the 80%. I guess I was more disappointed than I thought because next thing I know, I am crying. The nurse asked a couple of times if I was ok. How okay can I be if I'm crying? We went downstairs and tried to use the other machine and did the test the way I'm used to and it worked...I got the score I needed and I can participate in the study. YEA!
WHAT? Where did those tears come from? I am not emotional, especially in public. Needless to say, I was not expecting that reaction. The nurse probably wasn't either but she was very nice. Why is it that I cry when I don't want to but I can't cry when I want or need to release those feelings. I had to really fight to regain my composure. Usually I can "suck up" those tears if I think I'm going to cry and don't want to but today there was no stopping them.
Lately I've been trying to stick with the feeling and let whatever happens, happen. But good grief, I didn't really want the tears today.