I have been having chest pain,headaches,loss of balance,vision problems and general weakness is this a sign of brain tumour?

Nonspecific symptoms: such as you describe, can be due to many different disorders. This combination of symptoms are common in fibromyalgia (see: http://researchsolutions.online/fibromyalgia), or may be related to stress, physical or emotional. Depending on how long you have had the symptoms, and if symptoms are worsening, a brain tumor is a possibility, and can be ruled out by a careful eye examination or CT scan.