Then no, I would not super thrive yet. Superthrive is a stimulant, like a Vitamin B. It helps take up available fertilizer but it is not a fertilizer in itself. At 2-3 weeks your starters are not mature enough to handle that much accelerated growth. Give them 3 months or so and start fertilizing when they have put on some good growth. I look for the washed out color of the leaves before I start fertilizing.
That being said, I tried super thrive a couple years ago. I did not see any measurable results over a control group. Certainly no harm in using it. Figs don't need much fertilizer to do well. Too much nitrogen and you will get growth with no fruit. Don't forget the lime. Good Luck!