Betty, I just read you post and I hope you were able to get some sleep last night. Those are scarey moments when people ring the bell at night and the way those people were acting you were right in handling it the way you did. Sounds like they up to no good and sounds like you kept you wits about you. I hope you called the police back and had them do a check on the area around your house. What a scarey night for you.
I don't think I would tell anyone about the gun either. It may give some people incentive to get into the house to get access to the gun/guns. One thing I was told years ago, if your going to contemplate using a gun for self protection make sure you are ready to use it against another person, because if they get it away from you they will surely use it against you. I hope for me if I ever face that, my natural instinct for self preservation will kick in.
We had a guy ring the bell at 3am just a couple nights ago, drunk as a skunk my husband said. He was looking for the neighbor. By time my husband got to the door he was out on the sidewalk because he heard our dogs going off. We have a aussie/husky mix and a full blood aussie. The aussie mix has a really ferocious bark and then throw in the other dog and they get loud.
Like you I never answer the door to strangers, even in the day and even to people who look totally harmless. I keep my door locked when home to, my kids give me a hard time about that but I figure better safe than sorry. There are just to many weirdo's out there bent on doing harm.
I hope all is well for you in the light of the day. Keep yourself safe and nap today if you must.