The actress's character Sally Webster played one of the most significant roles in last night's special 50th anniversary broadcast, as she finally heard the truth about Molly Dobbs's affair with her husband Kevin.
In a tragic twist, Molly dramatically came clean to Sally before dying from the injuries she sustained in the street's tram crash tragedy.
Speaking during a webchat on Corrie's official site last night, Dynevor commented: "We've been rehearsing for two weeks. We never normally get that long. I was very nervous because I had so much dialogue.
"I sat in the dressing room on my own and tried to stay calm before the show. I've done theatre before Corrie, but this was much more daunting. The hardest part was the scene where I had the long speech with Molly."
She added: "The atmosphere was electric backstage. It was amazing. Thank you for supporting Corrie and keep watching - the next few weeks will be amazing."
Coronation Street's 50th anniversary celebrations continue tonight in a double bill airing at 7.30pm and 8.30pm on ITV1.
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