if you only upgraded in last few days, its possible its running extra services that will eventually stop running and return you to normal. expect it needs to install apps from store and recreate indexing.
We don't know what is using the extra so its hard to guess if its helping or not. I am not sure how we go about figuring out whats using the extra bits. My usage sits on about 21%
Task manager isn't the best way to track memory usage, I would download
Process explorer - its from Microsoft and is an OP version of Task Manager. It looks similar but default view is in a tree heirarchy showing what is controlling what.
If you run it, run it as admin so its got full access, and you need to look at the Working set column as that is ram actually being used by the process, Private bytes are the total of ram + page file being used by the process
this explains colors and meanings of columns, red isn't a bad thing: http://www.howtogeek.com/school/sysinternals-pro/lesson2/