That doesn't sound to good...Just to be safe run an AV and Spyware scan...
Always check your file sizes and use Bitzi it's a real life saver...
This link will tell you how to use Bitzi for checking reveiws about a file before downloading...
How to use Bitzi Web Lookup
This thread will tell you what to avoid and how to stay safe...
WARNING: Viruses on network you should be aware of!