HUGE SCARE - Need Help

I don't know how to go about explaining my situation, but here it goes. Last night I opened up my case for a moment to make sure it was clean and dust free. Thereafter, when I was connecting it back up to all the wires in the back, I may have made some mistake (I was doing it in the dark since my gf was already sleeping). When I plugged the power cord to the back of the case and turned it on with the power button, I heard what could be described as a lound sound resembling something caught in a fan, or metal scraping against metal. I then quickly pulled the power cord out, disconnected the case, opened it up to make sure nothing got caught in the fan (everything looked fine, no smell of burning, no visible signs of problems).

Upon re-connecting and booting it up, the boot up was slower. It started with the regualar blue Intel Pentium screen, and then when it proceeds to the "Please Select Your Operating System" black screen, it seems to hang for an extra 15 seconds or so. I did diagnostics with "Hot CPU Tester" and everything was fine. All programs run just as before and everything seems fine aside from that delay upon booting up as it transitions from the opening Pentium blue screen to the windows black screen. When it hangs the underscore just flashes for 15 sec or so. Please tell me I did not damage some hardware component, please help me out, as I am extremely nervous. Thanks you very much in advance.

 

Anyone?

 

Be assured that if the complicated box is working OK after boot up and all programs are Ok then you probably have not done any immediate damage.
As to the flashes on screen at bootup its possible you did not notice them prior to opening the case up and you now notice them fearful of what horror you may have inflicted upon the thing. As a jaundiced old computer fiddler and mini expert I would tend not to worry.
However I do worry that you opened your case up for a moment???? Surely, in the dark, gf asleep, it must have been longer than a moment.
It is not a good idea to go into these equipments in haste, in the dark, with a plan in mind for a quick fix for something that probably does not need fixing. So be assured it's probably all OK and best wishes to you and the gf and your computer for the future.
Happy NY
Robert