ten buy-in downswings are common.
it's normally recommended to play with 20+buyins at lower levels, and even more buy-ins as you move up.
By that logic, you're under-rolled even for 25nl...
Play 25nl until bankroll is >$1000, then move up to 50nl. If your bankroll drops to $320, then move down to 10nl.

read the stickied posts in the beginner forum, then go to the strategy section and read any article which has bankroll in the title.
If you're good, and it sounds like you probably are, you will get to 50nl pretty quickly, then getting to 100nl won't take too long either. At 100nl you could be making reasonable $$, withdraw it for a while rather than moving up - get a real understanding of what those $$ on the screen are.

good luck in this op!