Does my writing look like it's running downwards to you? I checked, in the scan the lines are perfectly horizontal. I think it's the way I hold my hand to get the right angle for the flex. Proper Spencerian pens have angled nibs so you don't need to do that.
This, the cheapest Noodler's flex pen, is finicky, has design flaws, and smells weird due to the plastic used, but with deliberation you can get results worth many times the cost of the pen, which only costs as much as an average bottle of ink.