Starting to get Social Anxiety

I believe I'm starting to get social anxiety. I used to not care what other people thought, but now I'm sometimes afraid to speak because I might say something stupid. I first noticed this when I suddenly had a memory and I said it out loud. My friend gave me a weird look and said, "Why should I care?" (the memory involved him). I was really sad for the rest of the day and was terrified of speaking. I never told him how I felt because I didn't want to make things awkward between us.