I had a chat today with a colleague who is also an introvert. Obviously after a while the discussion turned on how's it been working from home and not being able to meet other people. We both had the similar revelation that after first week or two in isolation we actually started missing all that social interactions.
Nobody is pure introvert or extrovert. It's a spectrum. We are all ambiverts, some just more socially inclined while others prefer solitude. There can always be too much, or little of both. The balance lies somewhere in between and that can vary between individuals.
I'm fine being days, even weeks all by myself. I know others who get anxious after just a day. I can spend days in the company of other people, but after a while I start longing for some quiet time. I believe it's the same for more extroverted people having to spend time alone. After enough time in separation even I start to want some more social interaction.