Live NL cash Game variance how many buys-in lost is normal?

[chipbrave]

Playing in AC $1/2 NL games I had 10 winning sessions in a row, averaging about $50/hour. Obviously I know this is not a large sample size, but I have since lost 8 staight buy-ins. Is this a normal variance in this game, or should I be concerned?
It has started with the usual stuff, loosing set over set, pkt As to pkt Qs, flopping nut str8 to lose to fh. flopping fh to get rivered by larger fh. Also I know I have made some mistakes in my play since this loosing has started, but I still think I'm playing a fairly solid game. In my game I strive to play "small-ball" poker. Not putting to much into the pot unless I have a very large advantage, and picking up as many small pots as possible.
So the bottom line is, whats a normal number of buy-ins that could be lost just due to normal variance of the game?
All thought would be welcome.