过度 (guò dù) means 'excessive, too much' and is used before verbs or nouns (e.g. 过度劳累, 过度消费). It is more neutral and formal than 过分 (guò fèn), which often implies disapproval or going beyond acceptable limits. 过头 (guò tóu) is used as a complement after adjectives or verbs (e.g. 吃过头 'eat too much'), not before them.