Hi, I'm sorry you haven't gotten some responses to your post before now. It's so hard to tell from just that one photo and your description. And a rose that is neglected/not growing well (not enough water, sun etc) can have smaller sized blooms...

Where did you buy it, or is this a found rose growing somewhere? What does the rose bush look like (tall? upright? bushy/spreading?) Do the blooms come in clusters or just singly like your photo?

Have a look on helpmefind.com/roses for pink roses and you'll see why it can be so difficult to ID pink roses ;-)

You might check out photos of Cecile Brunner and Souvenir de la Malmaison to get started. If this is not an old garden rose ("OGR") David Austin "English" roses has bred a lot of pink roses that resemble OGR's.

Good luck! Dawn

Here is a link that might be useful: Cecile Brunner at helpmefind.com