My dad used to work for a mortuary where he did the cremations. Many abortion clinics sent the aborted fetuses to be cremated, I believe because it was considered more sanitary. So it is entirely possible that the baby was cremated instead of thrown away.
As for why you didn't ask questions, you were in shock! You were shocked about being pregnant in the first place and then even more so with the aftermath or aborting. And passing out the baby/fetus itself and holding it would be extrememly shocking. Shock stops the brain from functioning as normal, so the questions just wouldn't have come. Don't let what you didn't have control over eat you up or cause unrest. What happened happened, and how you deal with it is your own private choice.