I totally bombed a particular class in HS. I honestly believe that horrible grade impacted my options for college;I got denied from all my reaches and what I thought were my targets. But you know what? It ended up being OK. In college I had the ability to avoid that subject matter, and I did fabulous in all of my classes and ended up going to a top grad school, doing well there and so on. Here’s the lesson I learned. Life’s always going to give you set-backs, and the people that succeed are the ones that get up, dust themselves off, and move forward. Also, there are many paths to success, so if one path is blocked, look for another.
So to answer your specific questions:
(1) maybe. But even if a bad grade impacted you, keep going and find your work-around. These things only keep impacting you if you give up.
(2) your future family shouldn’t have any interest in your past, unless you let that define your future. Also, people generally admire folks who overcome a negative situation.