Reverse Battery Connection?

Hi, I drive a Volvo S60 2.4L Turbo 2003, and last week, my battery started draining all the time, so I bought a optima yellow top, When I Connected (In the night without lights) I connected the battery terminals wrong, Positive to negative and negative to positive. (reverse conecction) all the lights of the car went on, and the horn didn't stop, so I removed the terminals almost inmediatly, I didn't realize at first the connection was wrong, so I got a lamp and saw my error. So I connected the battery Like it should be, the car started without any problem, just the stereo didn't work, thing I fix changing the fuses. Then I went driving and like about a hour later, the car computer showed "Low Battery", and 20 minutes later, the car stpped. The car drainned the battery. What could be the problem? I'm thinking about the alternator, so I bought anohterone, but my car mechanic, told me my car had a 140 alternator, and i bought a 120? Will this be ok? Do the alternator have a fuse? what would happen, I really don't trust a lot in mechanics, so I would like to have some info. Thanks

Many cars do have a fuse or fusible link between the battery and alternator.  My old Honda did.  If you did indeed connect the battery wrong, it would be in series with the alternator, rather than parallel.  The residual voltage left on the alt could have caused a voltage spike, which could have caused the amp draw to momentarily go up, blowing the fuse/link.  Check for this first, then test the alternator.My ex once told me I have a perfect face for radio.

I'd say you may have a short somewhere in the car. But firstly, I would check the fuse on the alternator.

I'd say you fried the alt. take it to have it tested. Most auto parts stores will do it for free.Big Dave