Please don't worry too much about it since you're feeling better. There are many possible causes of lip numbness, but the most common typically include allergic reactions, sensitivity, and mineral imbalances or deficiencies.
I had some numbness and twitching in the area around my right eye and having difficulty working, so consulted my Dr. He diagnosed it as sensitivity of the nerves underneath my skin due to anxiety. Sure enough, I was experiencing a bout of shingles. If symptoms persist and intensifies, best to consult your physician.
There was a time when I would search the web for symptoms I was experiencing and only caused myself more unnecessary anxiety. I don't do it anymore and am a much happier person
Hope you're feeling better . . . hugs