Plan b or no?

So I still have my period lightly but it's there when we had sex the condom broke and we didn't realize.
I had sex around 2am Sunday so it's still in the time frame I can take plan b. 
I also found out I have a bacterial infection.
Being where I'm at in my cycle still having my period and an infection doesn't that lower my chances of pregnancy quite a bit??
I asked my doctor and he said he's a pro life doctor and is against plan b but that my chances of getting pregnant are low... Do you think he's saying this due to being pro life or??? I just need some advice I'm anxious about taking the pill.