I’m glad to hear that it is working now, but just so that you know, you can change the From: email address while you are composing an email. The odds of you doing this accidentally aren’t all that great, but it is possible to do.
When you compose an email, if you tap in the From: field, and then tap again next to what email address currently shows when the window opens further, you can select from any one of your email accounts as the account from which you send the email. Like I said, the odds of you doing this without realizing it are pretty slim, but the point I am making is that you can change the email accounts form which you send the email while you are composing the email. I do it quite often.