Is this diabetes or hyperglycemia.

Today I went for a sugar test (after having morning breakfast, lunch and tea) somewhere around 1:00pm and i came to know that the  glucometer showed 358 !!! then I got my blood pressure checked and it was 113/68... I don't know wether it's diabetes or not ! Even I don't know wether this situation is serious or is it normal ! Some of the symptoms which I face are as follows :- I feel tired all day long. I also have pain and swelling in my legs. I feel uncomfortable. Even eyesight is getting weaker i.e myopia as well as hypermetropia (might be due to age) Under this condition which food should be avoided and which food should I consider ? What lifestyle changes are required? Which medicines should be taken in such case ? What should be the next steps to be taken in such a case ? What precautions are to be taken in such case ? Should I go for a sugar test empty stomach ?