is this sustainable?

hey guys! i am 25f. start weight was 198, current weight is 190. between january 15 and today,

i’ve lost a little over 8 pounds. i’ve been doing soft omad (i have 1-2 coffees with measured out half&half during the day) and keto, as well as increasing my steps from a sedentary level to 8k-10k per day. my watch says my steps/movement have me burning 500-600 calories a day. i’m only eating about 1000 calories, and it’s all fat and protein (and veggies!). i feel great, i don’t feel hungry, i don’t have cravings, and i’m losing weight. it’s been over a month and it’s just becoming part of my life. but everything i see says my intake is unsustainable. i take vitamins and prioritize nutrients in my daily meal. but is this a recipe for

disaster? i’d appreciate any advice, i’m anxious! thanks