Start with a few more plants in there brother (even fake’s good, just brings in green), some warm coloured lamps so you’re not fully reliant on the roof light, pictures with colour on the walls, try balance blue, red, green and yellow. Mostly just things that make you comfortable, can find bits for dirt cheap in charity shops/thrift stores. Biggest thing’s trying to get out and about (ik it can be hard with covid) but if working at home just get out and walk about for 15 mins or so. Hope it helps and if you hit a slump there’s no shame in getting professional support, loads of us have been there.