Hello, I Had A Unprotected Intercource Though The Spam Not

Hello, I had a unprotected intercource though the spam not getting inner side of vagina, on last month first week, & her periods was happened prier than 7 days on 23 rd sep. But still now one month over it's not happening, so with a confusion she did preg test on last 2days back, report was negative, so she takes modus 10 mg. is there any problem. & screed about pregnancy. So plz suggest me.