Well done for a good start. Keep going as you are, WD. The TDEE calculation is what you would eat to maintain your weight, so it’s a rough calculation of ‘calories out’, but there’s no requirement to put those calories in! If you eat less than that it will assist your weight loss. But don’t go too far down on non FDs, as this diet works partly on ‘shock tactics’. The intermittent reduction calms insulin, triggers fat burning, but if you just go low cal your body will start to conserve its systems and your metabolic rate will lower.
Make sure you are eating a good wide range of foods across the week on non FD days: meat unless you are veggie, lots of coloured and green veg, fish and sea food if you can, nuts, seeds, beans and lentils, unsweetened yogurt, cream, and plenty of fats as olive oil, butter or coconut oil. Try to use wholemeal and less refined grains like brown rice if you are eating higher carb foods. By doing this you will ensure you are getting vitamins and amino acids, the veg will also contain fibre and carbs in moderation. Don’t fear fat, it helps transport vitamins and reduces hunger. Concentrated and added sugars are likely to slow things so don’t drink fruit juice, eat whole fruit instead! Berries are good, also clementines.
There’s lots of advice on this site, so read Dr Mosley’s introductions and the thread “Advice for Newbies”. Good luck and keep hanging in here!