I have a lot of hyperpigmentation on my back and its looking a bit concerning? its also pretty itchy?

Skin issues usually require either a detailed description or direct examination with testing for assessment. Your description is too vague for an assessment of cause or potential treatment. Go get it examined.

You should have a Dr examine the area. It could be a fungal skin infection (Tinea versicolor) which can itch or not, can cause hyperpigmentation , & is usually easily treated , but there are a few other possibilities.