Sure, why not say that? And "I think..." is not what you preface a statement with when you're positive.do I say " I think i have social anxiety " as if im positive??
Take the Liebowitz Social Anxiety Scale and see how you do: http://www.socialanxietysupport.com/disorder/liebowitz/
You could even print out the result and hand them to your doctor. The fact that you're posting on SAS and terrified to talk to your doctor would make me believe that you almost surely have social anxiety.
I'd say you have a 98% chance of leaving the doctor's office with some SSRI prescription and quite likely a pile of samples that were dropped off by the endless herd of drug reps who regularly visit.
I'd say "don't worry" but I know you will anyhow because you have SA. Good Luck.