I think most of us if not all of us have experienced boners at times that we wish we didn't have a boner or at the very least have seen someone with a boner that was obvious. I don't understand the big deal. Men get boners; eventually boners go down. Someone sees you with a boner or a class sees you and it passes. If you don't make an issue of it, it is a perfectly normal thing to happen to a penis.
Someone posted this line above..........
Also, I wonder about the co-worker and his pre-occupation with my dick!
I don't think it's a preoccupation. Rather it is a guy who was not afraid to ask you a question that was noticeable to him. We don't look at guys to see if they have an erection, but sometimes if the erection is off to the side or str8 up or bulging noticeably, you cannot help but notice it. He may just be comfortable enough with you to ask you a simple question is all.
Don't be so uptight!
I agree with Redneckgymrat....
It's happened to all of us. All men have had this happen. It's no big deal...unless you make it a big deal.