Ready to TTC a girl

Hello everyone. I was on here a few months back and then disappeared as I was not quite ready actually to have another baby (my 4th). But now I feel in the new year it might be the time :).

When I started out back in June I was really strict with my diet and lost 2kgs, I don't have that much to lose. My main change was cutting down on meat, basically only have a bit of meat here and there on the weekend. I also stopped eating porridge in the morning (can't skip breakfast) and cut down on my dinners. Meanwhile as I relaxed my diet, I have gone up in my weight about 1kg. I still stick to the min meat and no porridge in the morning but have been having more chocolate and sweets and normal dinner portions.

I would like to start TTC now in January, I just ovulated (or so I think) yesterday, so have month to go. Do you think I still have a good chance if I do my best on losing that one kg again - after xmas :)? Coupled with the one attempt at the first peak reading of my ovulation kit?

Also do nail / hair supplements sway boy? I feel like I could do with some but am scared to take them. Have just started magnesium and folic acid again.

Thanks so much for any input.