These charts show the day-to-day increase in COVID-19 cases in Fairfax County and in the Commonwealth, through about 6 PM today, courtesy of the Johns Hopkins coronavirus information website.
The black line is a seven-day moving average. I’d have to say that, still, by eye, Fairfax does not look like it’s seeing exponential growth (like the side of a bowl). Instead, this looks more like a hilltop. And I’ll note that the break between concave-up (exponential growth) and concave-down (hilltop) seems to have occurred more-or-less at the right time for this to have been the result of the shutdowns and social distancing — a little more than 10 days after Fairfax shut the schools on March 13.
For the Commonwealth, by contrast, I’d say it’s still too soon to tell.