Could pre-cum get my girlfriend pregnant with only putting in just the head of my penis? I was fooling around with my girlfriend and one thing lead to another, we both got very horny. I ended up putting the tip of my penis inside her vagina, precum was a

To be blunt... Yes. Pregnancy possible. Only time will tell. Check a pregnancy test at five days if she misses a period or if the period is not normal.
Anytime . Anytime sperm comes in contact with the vagina, there is a possibility of pregnancy. Since pre-ejaculate contains sperm, it is possible for her to become pregnant if it touches her vagina and vaginal fluid - that's why pulling out is not a good form of birth control. I linked below to a website with lots of great, reliable information that may help answer any additional questions you may have. Good luck!