Our doctor gave our nearly 11-year-old son a Tdap shot. Except that when she pulled the needle out, a considerable amount of the vaccine spilled out of the needle. She didn't seemed bothered with this so I let it go. During the drive home I started to think about the fact that my son didn't get the right dosage. I called the doctor and left a message for her. She called back and said that yes, Riley would need to get the shot again and scheduled another appointment. She said she didn't want to alarm me right there. She said it would not be a problem for him to get a second, full dose along with what he received today. I really feel she should have spoken up right there. It looks bad when I have to call her and question her. I guess that makes me wonder about a possible overdose on Tdap. Is that possible? I can't seem to find any info online. Thanks in advance.