Hi mama,
If your general health is alright I don’t think your weight loss is something to worry about.
The general guideline is to consume 300-500 calories more - and mostly, it’s the quality of the calories you consume - good fats, less processed foods, proteins, lots of leafy greens and so on.
Alternatively, you could pay a visit to your gynae and explain what’s been going on. Being better informed about your health history, he/she might be better informed to guide you.
Happy eating mama!