Could this damage my sound card?

Several months ago I had reformatted my machine, and was in the process of installing the sound card drivers and applications for my SB Audigy 2. At the time, I had my microphone and speakers hooked up and turned on. I left to get a snack while the installation continued, suddenly I heard this extremely high pitched blaring noise coming from the speakers and I quickly rushed in to shut the speakers off. It turns out when the damn drivers initialized, it automatically set my microphone to max volume and then outputted through the speakers, creating a horrendous cycle of noise that I fear may have damaged something. I know the speakers are affected from this, but they're really cheap and not a big deal right now. What I'm really concerned about is my sound card, if this may have affected or caused any harm to it in some way.

Any opinions?

SUMMARY: My microphone & speakers were on and created a high pitched feedback of sound for about 20 seconds. Is my sound card damaged or affected in any way?

Is it broken? No? then don't worry about it. if it breaks, then you know you messed it up. K?