It seems like right now, when you think "social event" you think "alcohol". You're already trying to imagine new sober self in those situations and you're trying to work out how you'll fit.
Being an alcoholic myself, I felt the same way about 3 years ago. How would I go to my buddies' back yard BBQs, weddings, and get-togethers? Well, here's what worked for me: I didn't go. I removed the worry and stress and danger all together by just removing those events from the equation. We often neglect to even entertain that option - in fact sometimes we forget that we don't have to attend.
Congrats on Day 4. Keep it up! In early sobriety it's sometimes good to focus on the day in front of you, rather than on drinking perils down the road. All the best!