A. You're not alone. In the first video of his Calc I series, Professor Leonard cracks that "Calculus is the class you take to finally fail Algebra".
B. This is hardly unexpected, especially if there's any gap at all between taking Algebra and taking Calc. The simple truth is, you forget material you don't use. And most people don't use a lot of algebra in their daily lives. If even a semester or two has passed since you took algebra, you're almost certainly going to have forgotten a lot of it, unless you made a very pointed effort to keep practicing that stuff and focus on retention.
I successfully finished my CS degree.
But I often have the feeling that my math problems are getting in the way of getting on the next level, hehe.
Same here. I hate finding amazing CS academic papers and trying to implement them, only to get stuck at some high level math formulas.
Some of the best software engineers I know went from a math background to software. I guess I'm going to have to catch up.
I'm not sure I have any suggestion other than lots of practice. And know that you're not alone, this is a completely natural difficulty.