Yea I agree with ohthejoy. I would mention it to ur doc. Also do stretches & perennial massage. Kegels are good try to stretch out that area.
I'd go to a doctor, could be something as simple as a yeast infection (trust me, they burn!) Otherwise you could try perennial massage to kind of "stretch" the area if it is getting tighter. Hope it goes away soon! The things we go through...such a wonderful reward at the end! :)
I suppose you might have tightened up a bit in general, seeing as you're having sex less frequently. Also, I noticed that there is a lot of swelling all over down there for me, and sometimes I can't even fathom the thought of SO fitting lol.
You might tear or might not, in my case with my first, I did tear (I had an epidural), but I didn't even feel it. All I could feel was the massive relief of getting that baby out of there and it was awesome. I did have to have stitches, the nurse gave me a shot of lidocaine or whatever before she started, and it still hurt some, so I asked for more. After the third, she told me it was legally all she could give, and by then, I could still feel her stitching, but it was very faint and didn't hurt. It felt like very soft pinching and tugging, it was nothing to worry over at all.