See a psychiatrist, for sure.
On awkward silences: when you meet the psychiatrist, remember that it doesn’t have to be a conversation until he/she decides to make it one. It’s about you — the shrink will respond to you later. Just start talking and keep talking until the shell you describe starts to crack.
Once you make that crack, I’ll bet the tension inside you will take care of pushing out the rest of the talk the shrink will need to diagnose you. Don’t even think about avoiding embarrassment or keeping secrets (unless you murdered somebody or something) — just let it all flow. The shrink has certainly heard much worse.
Meds may help that shell crack some more, and then maybe a dedicated therapist will do you more good. But what others say above about a match is true. And therapy may not be necessary. Meds may help you lift and carry the weight. Let the shrink guide you; he or she can see things in you that you can’t.