Thanks for writing to us.
In my opinion spotting may be because of I-pills because chances of pregnancy
are rare in your case because you have not ejaculated inside and she had I-pill within 72hrs. Of sex.
Yes, she can do a pregnancy test on the 22nd that will give the correct result about pregnancy.
You should consult a gynaecologist for ultrasonography
to rule out pregnancy when she missed her period.