Period missed by 3 days. Doc, this?

Hello Doc, This regarding my to be spouse. We had our private moment but i did not ejaculate d inside her. It was just outside but yes touched her private area. I am aware of the fact that i should have taken care of this and used condom but it just happend in the moment. Her mensuration cycle starts from 27 of each month but after this incident she missed her dates by 2 days and no symbtoms yet. We are really concern whether is there any chance of pregnancy? How to check/verify ? Or it is just the tension and thought we have in our mind. If by any means test comes positive, as we are not ready yet how can we avoid this. Please guide because i am really very much tense considering our future. Incident happened on feb 18 and it has been like 2 weeks now. Please guide us how shuld we proceed ahead with this. Thanks in advance.