Hello I'm 20 years old and today I decided to test...

Treatment of high level glucose:
According to your question, you need to control your glucose level very well by conservative management by avoiding any sugar-containing food of drinks, and by changing insulin dose and it is better to go to hospital to start sliding scale control of your glucose level in which insulin level is adjusted according to your glucose level.
Diagnosis of Diabetes:
It depends on the clinical examination by internal medicine doctor and investigations as randon blood glucose level, HbA1c level, renal function tests, cholesterol and triglyceride level, urine analysis...etc
Symptoms of diabetes:

• Increased thirst
• Increased hunger
• Frequent urination
• Weak, tired feeling
• Dry mouth
• Blurred vision
• Numbness or tingling in the hands or feet
• Slow-healing sores or cuts
• Dry and itchy skin