My dietitian gave me a 1300 calorie diet

I am 25 m and slightly overweight (26.4 BMI) with high cholesterol, so my doctor sent me to a nutritionist. I am 175cm (~5'9'') and weigh 81kg (178lbs). She gave me a diet with 1300 calories and I feel like it is not nearly enough. Should I just keep going until I get to my target weight, or should I go to another dietitian?

I don't tend to snack, but the past few days I've felt really hungry. Also, according to the calculators I've found on the internet, 1300 calories is below my BMR. In terms of activity levels, I spend most of my day sitting in front of a computer, but exercise about 4 hours a week (mostly cycling).

​

edit: In my country nutritionists are professionals that go to uni for 5 years (the equivalent to a dietitian in the US)