Solved Mystery plant - Mazus Reptans

Hi there
I bought a beautiful plant today from my local garden centre, but it's a bit of a mystery! There was only one of them and it didn't have a label. The man thought it was some kind of perennial lobelia, but I can't identify it. Does anyone have any idea what it might be? (Hoping the attachment works!)
Thanks!

 

it reminds me of Viola , are the leaves the same as these ?

 

I can't grasp the scale, it looks very similar to lobelia but seems bigger - what are the flower/leaf sizes?

 

Thanks Spruce, but fairly sure it's not a viola - the leaves are longer and narrower than a viola.

Madahhlia, the flowers are between 1 and 1.5 cm across and about 2cm long, the leaves are about 1.5cm wide and the biggest ones are about 3cm long.

 

its not lobelia as its to early to flower unless grown in a greenhouse , and chance of a side shot of the plant and put a 50 pence piece next to a flower to judge the size better,

are you in the UK ?

 

I am in the uk!

 

It's Mazus Reptans

 

Clever Fern well done you

here a little more about it , being nosey how much £

thomson and morgan selling 5 plugs for £14.99

This hardy little alpine is surprisingly tough and spreads quickly to create dense mats of ground cover. The low growing foliage bears pretty purple flowers with attractive, yellow-spotted markings from May to July. Mazus reptans makes a lovely spreading perennial for carpeting rockeries, or creeping through alpine troughs and gravel gardens. Height: 5cm (2”). Spread: 30cm (12”).

 

Spot on, Fern, thank you!!
Funnily enough, it was in the Alpine section and they were 3 for £5!
Thank you guys for your help!