Pill and Blood

Hi,
I recently started having sex with my boyfriend. I had never really had sex before (there had been attempts but no real penetration beyond 1-2 inches). I have taken Ortho-Tri-Cyclen Lo for a few weeks now and am good about taking it - I don't take it at exactly the same time each day, but take it within 1-1.5 hours every day. I asked my doctor about this and he told me it was fine.

After intercourse last week, I noticed some blood on his condom (we were still using a condom to be safe since it was only 1 week after I started the pill). It wasn't a large amount, but enough that we had to wipe it off using a napkin. Looks like fresh blood.

I asked my doctor who said it's probably spotting and the pill was still effective. Not to doubt what he says, but is it true? Should I be worried/take other precautions? My biggest worry is whether the pill is still effective - we have had sex a couple of time afterwards without a condom, after I had spoken to my doctor.

My bf took an STD test and will receive results in a few weeks - think it's unlikely (but obviously possible) he has any STDs given his last test 6 months ago. I certainly doubt I have STDs given I was essentially a virgin.

I realize it may have been some of my hymen being torn, but it was not the first time I had sex with the current bf (maybe the 3-4th time) and there had been no blood before.

Any help greatly appreciated.
Thanks.