I am a CPR instructor and still amazed at how many people have not taken basic first aid or CPR that are otherwise very well prepared for most contingencies. For me this was one of my first priorities and it actually lead to a part time career as an EMT for a local city.
Too many people get on forums and ask for feedback on their first aid kits, and yet have no training to use half of what is in their kits. Also, many people's first aid kits have not been even opened since they bought them. Any kit that you rely on should be opened and used, even if only for practice at least twice per year.
I am glad to see that you are remedying that hole in your preparations.