You can be very cautious but still catch it - HK has only just started easing up on its 1restrictions (e.g. my flight was cancelled this summer due to COVID (not mine) & I had to isolate for a week as soon as I landed - after testing negative both before & after the flight, mind you!) but we're *still* instructed to wear face masks everywhere (except to exercise & eat).
So despite being quadruple vacced (the current maximum here), wearing my mask the entire day (when teaching), it just took my husband's deskmate to come back to work a *week* after testing positive (since he 'felt fine' by then) for me to catch it too
This all to say please take the time you need to recover! I tested negative after 6 days but, like Joy's friend, I'm still finding I'm forgetting stuff & my work output has slowed, even now... (forgetting words can be very disconcerting when it's your livelihood!)