Somethings wrong with my tomato pls help

[iluvnature124]

its been growing a lot like, 2 weeks ago, but stopped. the leaves keep becoming curled up and some older leaves are dying. im thinking maybe not enough sunlight.
iv also noticed the dirt is very like concentrated, like its all hard. purpleish stem too.while the stem is kinda purple, the new stuff growing from it isnt. the stems been purple for a while now, maybe a month or 2, and it started the same time as the curled leaves.
we can see that some much smaller new sprouts are growing from the stem too, though they stopped, and the leaves are kinda wrinkly too, all bumpy.
with the stem sticking out from the plant, the one with the wilted leaves, the leaves that died did so like a week or 2 ago, but like the other stuff, its stayed the same since.

 

[smitty55]

Purple stems and leaves on tomatoes are usually a sign of lack of potassium or could be from excess watering which can cause root rot.

 

[Oliver Buckle]

Over watering will wash nutrients out of the soil, but there is also the possibility that it is a bit cold which would stop it taking up the nutrients even if they are present in the soil. Looking at the plant though the main thing that struck me is that it is 'strung out' and 'rangy', as though it is not getting enough light.

 

[DiggersJo]

I agree with what has already been posted, but there also appears to be a tree sapling growing in the pot (3rd picture). If it is that will not help things.