Hi Helen,
A few months ago, I started a thread because I had the exact same concerns as you. But guess what? I've been to both my doctor and dentist since then! You absolutely will be able to, it's not a question of if but when.
In Australia at the moment, there's a big campaign raising awareness of the importance of early detection in cervical cancer. It encourages women to get tested with a few friends to make it less uncomfortable, and afterwards they'll go out for lunch. Maybe if you had someone with you, going to the doctors or dentist wouldn't be as scary, because you know that person wouldn't go with you if they didn't think it was going to be okay. It's reassuring.
I'm worried about going to the hairdressers (you can't exactly leave halfway through if you start to feel anxious so there's no escape) so I might ask a friend to come too.
Working through the Anxious Thoughts challenge sheets help so you have something to come back with when those anxious thoughts try to take over.
All the best,
Kaitie.