Mensuration problem. It the whole month!

Me and my girlfriend used to have genital grinding alone for past few 10 months.. no ejaculation and no penetration.. and i wont touch the tip of my penis near her vaginal hole.. and she is a virgin..her age is 23 She always have light periods since her puberty.. during 26 to 30 November her periods was very very light...last time we were genital grinding around November 11th.. during December her periods didnot come.. she went for consultation on December 30 ultrasound shows every is normal.. in blood test negative pregnancy.. and yesterday(jan 7th) we took home pregnancy test it was also negative.. In blood test TSH level is 0.132 mlU/L can this be the reason of late periods.. am scared she is pregnant.. Can someone become pregnant without penetration and without ejaculation near her vaginal opening... And i dont finger her since she is a virgin.. Please help me am dead scared.. am thinking about it the whole month