Please identify my tree - pic attached

[Watellz]

In the UK. Currently in a pot and about 2ft tall.

Presuming it needs planting in the ground but need to understand what it is first and how big it might grow

It looks like a Small LeavedLime ( Tilia cordata, but not 100 sure...

Is it supposed to be that colour? looks like it's short of magnesium to me.

Hedgesfullofbirds that's it. Will need to find it a new home as much too big for my garden :-(

I disagree. I think it is a cercis, or redbud tree. Possibly eternal flame?

I don't think the bark is right for a lime tree?

https://www.ornamental-trees.co.uk/products/cercis-canadensis-eternal-flame-tree

If it is then you are lucky because cercis are stunning.

They also are quite small trees

Geneticsbunny your suggestion is lovely and the leaves are the right shape. However mine's a lime green yellow colour.

It could be a different variety but I am reasonably certain it is a cercis because of the leaf shape and the bark. Could you take a close up pic of a leaf so I can double check? Also, with eternal flame the leaves are only that orange/rusty colour when they first emerge and in autumn. The rest of the time they are lime green. I would take a pic of my one but it is in shade and I am up north and the leaves haven't emerged properly yet.

They can have a huge range of leaf colour. I have a purple leaves one called forest pansy.

I was also thinking cercis. Did it have any flowers on the bare stems before the leaves appeared?

Geneticsbunny leaf picture attached

MadameBethune not sure about flowers. I wasn't paying it much attention

Please water it, or you won’t have to worry about where to plant it.

I don't think it's a lime - I've got 2 in the garden and the leaves are different.

Yep. I am sticking with some sort of cercis. Maybe this one?
https://www.greenleafnursery.com/index.cfm/fuseaction/plants.plantDetail/plant_id/2982/index.htm