Can Non-penetrative Sexual Activity Cause Pregnancy?

Hi Doctor. Can I just ask you about my problem. I had dry sex 19 days ago. I still had my underwear but he had nothing. But he didn t ejaculate on me. I m still a virgin haven t had sex before. It happened 5 days before my period. I still had period 5 days after that but it was just not like usual it was less than usual. I have breast pain for someday after that. I used the pregnancy test for the firsr time 10 days after that it was negative. 5 days later I tested again it was negative and today it s been 19 days since I did that I tested again this morning it was negative again but the thing is days ago I saw something like a linea nigra on my belly. Is it a symptom of getting pregnant? I m so scared please reply me Doctor. I m 20 now.