Well, to provide some balance, while I experienced lighter than normal period after my second shot, my 16 year old son had an unusual bleeding occurence 3 days after his that is now being investigated by his pediatrician in consultation with a hematologist after a blood test revealed unusually elevated PTT and INR values (part of the clotting cascade). We are going to follow up with more testing in 2 weeks to see if the levels return to normal and to check for a few more things (Factor 7 and some liver function tests). The hematologist would not definitively rule out the vaccine being the cause, yet, although she had not heard of something like this happening in 16 year old vaccine recipients. Maybe my son will be pediatric "patient zero" with this particular issue? Who knows. I just know that prior to this shot, he didn't bleed heavily for 25 minutes after picking, essentially, a hangnail. But he did last week and it was very alarming. He habitually does that and never bled like that before the second shot, so I don't know what else to blame it on.
That said, I have NO regrets getting him vaccinated and will have no reservations when it comes time to get my 15 year old vaccinated.