Hello Josh
It will likely look a bit lighter because it is being bleached by the sun as it grows out. It won’t be any finer (or coarser) however, because shaving can’t achieve this. If you prefer finer hair you may want to consider laser which helps in this regard.
Shaving different parts of the body for the first time is tricky, because irratation is a problem. The skin is not easily forgiving and a lot of time is sometimes necessary to get used to shaving. The itch you described does eventually go away as well as the red bumps.
I had the same thing for nearly 2 months when I first shaved for cycling. Today I shave every morning (face and legs) as a routine. My skin is so used to shaving that if I forget or am in a rush and skip a day or two my legs get itchy with red bumps coming out - exactly the opposite, which shows how skin adapts.
When I started shaving my legs permanently, I did it in summer when I had some leave from work. This was so I could wear shorts almost every day to let my skin get used and I think this helped. Long trousers (particularly jeans I found) cause rubbing and aggrevate itching and razor bumps at first.
For shaving legs all I can say is that you must stick with it to see the benefit and shave regularly and often.
Regards
Stuart