Can my girlfriend be pregnant from pre-cum even when she had her underwear on

Patient: Respected Doctor,Me and my girlfriend were fooling around on 8th Feb, she has her next period scheduled on 18th Feb (25 day cycle).She always had her underwear on so did I and I never ejaculated. The only fear we have is even we had our underwear on we got involved into dry humping, can Pre-Cum still penetrate inside her underwear and make her pregnant (I urinated quite a few times before I masturbated the last time) So is there anychance of pre-cum containing sperm and penetrate her underwear.We both are very very tensed and she complains of some regular pain down there from last 4 days and according to her she has never had this kind of pain in her life (She is 25 and virgin). We will never ever get involved in this kind of act in future as we are scared to death this time we have strict families.Please let me know if I need to provide any more information. Many thanks for your help in advance.Kind Regards,