Mozz - // It's possible Sheena's one was influenced by Dolly's, especially considering Dolly's wasn't a hit in the UK. //
Unlikely - they were both released at virtually the same time.
If you are a British songwriter, the last thing you want to do is title your song with the same name as the latest release by one of the biggest stars in the world, the confusion hurts your sales, and your credibility.
If you are Dolly Parton, you don't need to bother taking titles off other writers.
Like I said, coincidence.