could I be pregnant?

Hi guys. My boyfriend and I have not had sex- we want to get married first. However, a few nights ago, we were in bed and touching each other. He jerked off and afterwards proceeded to finger me, then ate me out. 
Could this cause a pregnancy if his fingers were covered in sperm? 
I don't know why, but after that encounter, my vag has been very itchy and burns. It's an uncomfortable feeling that I never experience. Why is this happening? 
To wrap it up: Boyfriend fingered me, could I be pregnant? 
Vagi has been itchy and burning for several days after that encounter, what could this be?