well ive not rode a bike in about 20 yrs..

hubby bought us bikes on monday.. I rode 4 miles today (yippee) down to a local church.. I didnt eat before i rode, but drank about 20 oz of water

on the way there it was alot of coasting with a bit of cycling.. there is a huge hill that i only got 1/2 way up (very difficult to walk up let alone ride)..

the way back is just the opposite (of course) with little to no coasting.. still only got 1/2 way up that hill..

round trip took me about 30-40 minutes

how do i calculate the calories burned?

how do i plug this into fitday? I know there is a place for activity but if i plug in 4 miles at 30 minutes, wont it just mistake that for faster MPH? or is this ok since on the way back it is double the work?

is it normal for a beginner to feel like when she gets done? and will this go away? (I do feel better after sitting down for 10 minutes and drinking water.. is it simply that i need to carry water with me?)

to avoid the ouchies.. whats the best type of seat to get (i read someone got a gel seat)? and what other things should i get.. gloves? water bottle?

thanks in advance for all of your help.. heres to better health and not getting winded on a bike ride !