Ответ:
2. A: I have got a headache
B:You should've not went to bed so late.
3. A: I failed the test
B:You should've studied more
4. A: I have got a cold
B:You should've worn warmer clothes
5.A:I haven't got any money
B: You should've not spent it on CDs
6. A:I'm tired
B: you should've not played computer games all night.