While bulls always welcome big price gains, Friday's action didn't look so strong under the surface. Lower volume suggested that funds weren't fully participating. And action among some leaders involved negative reversals and stalling.

Stalling involves heavy volume without price progress. It points to funds selling into strength.

The uptrend remains under pressure. The market has notched four days of fast-trade selling in the past 12 sessions.

How should individual investors react? Let the uptrend prove itself before you buy aggressively. Defense should be No. 1. You don't have to dump stocks en masse, but lean on the side of protecting your capital.

With the uptrend that began in March 2009 near the two-year mark, bear in mind that historically the market has a tougher time making gains after the first two years of a bull market following a major decline.

Even if you regard this as an abnormal bull market, it's prudent to keep your expectations in check. That can be a struggle. It's only natural after big gains in 2009 and 2010 to become bold.

Erring on the side of caution is wise after the big money has been made, even if you weren't the one making the big money.