Is it finally time for a doctor?

It seems on the road of running, injury, and recovery - as in life - there come times when a crossroads appears in front of you, urging you to make a choice.  I find myself at such a crossroads.  

It's been almost ten weeks since I first noticed my shin hurting after an eight-mile run on Halloween morning, and it's been almost five weeks since I stopped running and started cross-training.  While cross-training seemed to possibly be helping, after doing my crazy, ill-fated power walk a week and a half ago and after introducing some short running stints into my regimen, I feel the shin has gone back to square one.  

I am finally at that crossroads of What to do?  There seem to be four choices: 

1. Keep doing what I am doing, including the running, and hope that the body will sort itself out eventually (which would actually be my preference)
2. Go back to exclusively cross-training and try to reattain those pre-power walk good vibes
3. Go in to see the PT ladies who helped me so much with my hip last year for an assessment
4. Go to a doctor

I hate going to the doctor, because my experiences in the past have been that they either just tell me to RICE it, which I have done, or they'll want to order some very expensive tests.  On the other hand, I have a marathon in May that I don't want to give up if I don't have to, but I also don't want to soldier through it if it will make the situation worse.  There are bigger goals ahead later in the year, after all.  And, also, I have now had enough people say to me Oh, geez, do you think it's a stress fracture? as to be worried about it.  I blew off that notion for quite a while, but I have had enough people mention it now that it is all I can think about.  

Distance Dude says he'll eat crow if it is a stress fracture.  (So, as you can imagine, it is almost worth having that diagnosis.  Ha ha ha.)  He thinks that I should just keep cross-training until such time as it doesn't bother me anymore.  But how long do you do that?  I am losing patience and focus.  What to do.... If you are hurt, when do you know it's time to see a doctor?