Emotional, crying for no reason, is a fairly common pregnancy post, as is unusual fatigue. Changes in breasts, nipple, appetite, smells, feelings of nausea all get mention. It sounds like her next period is due about now, so a pregnancy test next weekend using first morning pee is in order.
A pregnancy may cause a woman to act in unaccustomed ways. Try to be understanding
Ugh, the pull out method is, unfortunately, not a way to prevent pregnancy. It makes a tiny bit less likely but it still can happen. A penis will emit small amounts of sperm during intercourse before the full ejaculation and it is 'enough' to get someone pregnant. However, this would be very soon for her to have any symptoms of early pregnancy. They will start around when her period is due. Do you have any idea where she was at in her cycle when this happened? That can be helpful information. But normally, it takes a little bit of time for the hormones created by being pregnant to result in noticeable symptoms. AND, PMS has similar symptoms. It could be that. OR it could be all the stress going on in the world right now with the pandemic. Lots going on. A pregnancy test is accurate starting at about 2.5 weeks after the episode. AT that point, she can take a test if she hasn't gotten her period. But my guess is it is on its way. fingers crossed for you both.