Congrats on your sales!
The hardest thing is convincing yourself that you really can get a sale. Well now you know that you can, and your sites are as good as any. My advice would be to build build build. Remember that the link lists are really yours in a way. If you submit quality each day, soon you'll have a site listed on them all, and for each day of the week. Their traffic becomes your traffic. And since you're listed monday to sunday, on all the best lists, what traffic!
So my advice is keep doing what you're doing (cos its making you $$$). Get your sites listed each day and hone your skills as you go.
All the best!
