Had clear ct in 2011 for daily headaches, nausea, appetite loss and tingling/numbness left side. still no diagnosis. brain tumour likely?

Not likely: Your brain ct was done in 2011. At 25 the types of brain tumors people get are rare and would have made their presence known by now. (dead woodchuck) a benign mid- line falcine meningioma coud produce left foot symptoms but would not likely cause appetite loss. Might be time to have another look (what's causing the headaches, left sided symptoms and nausea ?) ct: benign convexity meningioma.