DD has been there. What I suggest is to back off all the rest of EC/potty time when she's awake except for right after the morning wake and naps. Do this for a week, then add EC/potty immediate after her main meals (for dd it's 3 meals). If you still have problem, write back.
For me, if dd want to nurse while on the potty, I let her. I get down on my knees (her & potty on one side of me or sometimes in from of me) and bend over for her. Do you understand?
: I also want to add is that when dd wakes up, I would nurse her first. If she wets her diaper, it's ok. But right when she's done eating, she will either get up herself or have her eyes wide open with a smile. It is then I will immediate get up and run her to the potty. In the beginning, I will always miss that morning pee, but she will get it in a week or 2. Don't worry about it. After naps, I will tend to rush her to the potty (before nursing) and if she wants to eat, I'll feed her there. But you can also distract your child from nursing by singing songs or reading books (if nursing position is uncomfortable for you).
Also, is your dd teething? I know when dd teething, I have a lot of misses. Don't worry so much about it. Is she sick? Sorry so much questions - just want to understand the situation better.
Good luck and definiately DON'T QUIT ECing! APing and listening to your child's need can start at any age, but it will have to be consistant to have it successful.