Confused if I should get a rail pass or not

I'm trying to work out where the trains go and if I should get a rail pass
We land in Narita airport on the 18th of May and we leave the same airport in the 1st of June! So this is what we're thinking of doing!
Day 1 - night in Tokyo
Day 2 - train it to Osaka - explore Osaka that day were staying in the main city
Day 3- universal
Day 4- Osaka aquarium then train it to Kyoto
Day 5- explore Kyoto
Day 6 - see temples and go to Namba
Day 7 - train it to Tokyo - explore surrounding city's
Day 8 - Disneyland
Day 9 - Disney sea
Day 10 - find the mega Pokemon center and explore shibuya and other areas
Day 11 - explore more Tokyo
Day 12 - train and bus it to more parts of the city
Day 13 - train it to the airport

I iust want to know is the jr east pass goes to all these places or if it's worth me getting a pass in genera and if ill be saving any money ? Please help!!!