I would contact your doc. It is probably nothing. I can say that some of the strangest things pop up when you are pregnant sometimes. So, it very well could be from your pregnancy. Or it could just be a cyst that will go away on its own. But you never know, so contacting your doctor would probably best :)
Sometimes itching increases with the increase in discharge that occurs. It can sometimes cause extra irritation to an already sensitive area. However, just to be on the safe side, I would definitely have the doc check to make sure that is all it is. If it is some vagisil works wonders.
Perhaps a yeast infection? I would definitely talk to the doctor's office and have them check it out and recommend some safe medicine (you might be able to use Monistat cream if it is a yeast infection).
If you have/had a bump, I would go to the doctor.
You may have an std that didn't rear it's head until pregnancy? Did you already have all of your pregnancy testing done? My Dr. tested for everything!! OR, possibly just an ingrown hair? I would still consult your Ob/Gyn. Better to be safe (and not itchy!) than to wonder. Plus I get very nervous about meds now that I am pregnant and what is safe vs. what isn't. That is what the Dr.'s are there for,so I would go and have it checked out. Even if the bump is now gone, it sounds like you still have irritation and maybe a Dr. can figure out what's going on!?
Good luck and keep us posted?