Nothing Special

Idon't know if this is anything to be concerned about, but it really freaked me out.

The other night I was coming home from my computer class. It was around 10:15 that night. I have a 11 month old son, and he was at home with his dad, so I had the radio up pretty loud (anyone with kids know where I'm coming from :)) Anyways I was about a mile from home, (I live in the country) at the corner of Pinto Rd. and hwy 7. On one side of the road its dark, on the other there is a security light at the cable place. It wasn't pitch dark outside, there was a little light from the moon. Anyways on the passenger side of the car I noticed a black cloud. It was just a black shape of something like a comet would look like in space. I saw it for maybe 5 seconds. I don't know what it was but needless to say I turned the radio up louder and drove faster...a lot faster...home. When I got home my husband told me that he sees that all the time. He just figured it was some kind of fog or something. like I said, this story isn't anything special but its what happened.