I am terrified. Please no rude comments. I need help

I need help from the more experienced women on here...
So I'm young (19) I was homeschooled so I never got proper sex Ed. 
In September, I had what's called dry sex, dry humping, outer course with my boyfriend and he wasn't wearing anything and ejaculated right on my jeans!! Near the crotch area!! I was wearing jeans and panties. I've gotten 4 periods roughly about the Same flow and at the time but I'm so afraid because some women on here tell me I could be pregnant😭😭😭😭😭😭😭 I hate this. I NEED HELP