Congratulations on landing your first order! That's definitely a milestone worth celebrating, especially without any reviews or portfolio samples yet. I totally get that mix of excitement and uncertainty you're feeling right now.
I actually had a similar experience when I started on Fiverr. After my first successful order and 5-star review, things really started picking up momentum. Before I knew it, I had reached Level Two seller status, and even now, despite not being super active on the platform or doing it full-time, I still get frequent order requests. It's pretty amazing how that first positive review can kickstart things.
Your game plan sounds spot-on. Focusing on absolutely nailing this first order is crucial - that initial review can make a big difference in how potential clients perceive you. I'd definitely prioritize delivering exceptional work over rushing to get it done. Then, yes, adding some solid sample work to your portfolio will help give future clients a better idea of what you can do.
Just keep in mind that even with a great first review, the order flow might still be a bit unpredictable at first. Fiverr's algorithm seems to favour sellers with more reviews and consistent work, so building up that momentum can take a little time. Don't get discouraged if there are some quiet periods - that's pretty normal in the beginning.