Hello Marcus and welcome to the Aikiweb.
There are a few threads from some months ago that dealt with dizziness from rolling. I used the "Search" link at the top of the page and used the keywords "dizziness" AND "rolls" and came up with this:
There were a few others threads there as well, so you may find a lot more information than you bargained for.
Hope your knees and ankles feel better from sitting. I used to sit (seiza) in a hot bath, it helped relax my muscles and the joints a bit more when they were warm.
Hope this helps,