Well, maybe it's an Ohio thing........... the neighbor walking in, I mean. Some of us neighbors are also really good friends, and we DO just walk in to our friends' houses. Has anyone ever seen "I Love Lucy"? : )
We know when it's okay to do it, such as after breakfast when it might get us a cup of coffee, or in the evening when it will probably mean a glass of wine. : ) We do it when it's the daytime, and we are sure that everyone is dressed and we have a good idea of what is going on at that time. We do NOT do it when it's dark (unless our neighbor/friend knows we are coming) or if we see there is company or we think something might be going on that we are not part of and is none of our business. I guess we just know each other well enough to know that.
Some of us (not everyone here does it) grew up doing that. So it's normal to us. Again, this is only if we are good friends with the neighbor. We don't just walk into EVERYone's houses! So I don't want you all to be afraid to move to Ohio if you ever have to! ; )
Back to the question - the only thing I think is weird is that all of a sudden she was in your face. ? Why? And did you get the rotten taste in your mouth AS she was talking to you or did it come later? It is very weird. As everyone else suggested, see a doctor. And let us know what it was.
Blessings.