You will be using a couple of different endpoints to satisfy this use case.
A. To create a Tweet, you will have to use POST statuses/update. If instead, you are trying to locate a Tweet to track, you will likely be using one of our Search APIs.
B. If you are trying to track these statistics from a user that you are authorized to access content on behalf of, then the Account Activity API will be a great option for you. You do have to subscribe to the user who published the Tweet that you are aiming for and they have to provide you permission to access these stats.
If you are trying to track these stats from a user that you don’t think will authorize your application to access their information, then it will be slightly more difficult. We have some operators available with our Enterprise PowerTrack product that would help you track these stats:
in_reply_to_status_id:
retweets_of_status_id:
retweets_of:
is:retweet
is:quote
The free option here would be to use the statuses/filter streaming API to try to track this information, but that gets dramatically more difficult.
I can’t help you too much with the delivery via email situation.