Brief Answer:
Depends on the infectivity of your colleague at the time of contact.

Detailed Answer:
Hello, Thank you for using "Ask a doctor" service.

I read your query and I understand your concern.

It depends a lot on how much infective your colleague was at that moment. There are people who got very few contact and got infected and others who slept in the same bed and didn't get infected. This is really a weird virus.
From what you are describing I would say it is almost impossible you got infected, considering since her boyfriend is asymptomatic then maybe he himself is very less infective. But again you never know.
Me and my husband stayed for one hour in the same room without masks with a symptomatic person which coughed multiple times during that time, and we didn't get it.

So definitely I would say decide yourself how much this is going to affect your life. Keep distance from people who are at risk, eat healthy and drink plenty of fluids, take vit D and eat a diet rich of vit C foods, take walks in fresh air. If your colleague tests positive then follow the rules of the country where you live.

Hope this is helpful. Let me know if I can assist you further.

Kind regards, Dr. Klarida Papaqako, General and Family physician.

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