Pretty much.
Upload is when your PC sends a file or other data to somewhere else on the Internet.
Download is when somewhere on the Internet sends you PC data. Could be a file, or a webpage for you to look at, whatever.
If you can not identify the reason for sending more data then maybe you need to keep an eye on it. Perhaps, for peace of mind, run a virus scan and a malware scan. 1.7 Gig is quite a bit. (Did you connect to another PC via the Net ? I've found out that runs up data use.)