Slow weight gain in BF ex-preemie?

[PretermMammy]

I was wondering whether anyone could help?

Dd was born at 29 weeks and is now about 5-and-a-half months corrected age. After a period of feeding her EBM by bottle, she's been exclusively breastfed (until two weeks ago when we started introducing small amounts of solids). It was a tough start, but she's been doing really well and I'm so pleased to have been managing to breastfeed her.

Anyway, today I had my dd weighed and measured at our GP, and I'm a bit worried that her weight gain has slowed down too much. Apparently, her length and head circumference are on the 50th centile for her corrected age, but her weight is now around the 20th. About three months ago, when we last had her weighed, it was around the 50th (as were her length and head circumference). For info, her weight three months ago was 5.6kg and it is now 6.6kg. This strikes me as quite a slow gain, but my GP said she wasn't concerned as dd seemed healthy and alert. She seems to be meeting her milestones okay for her corrected age, and she doesn't look skinny - people always comment on her fat cheeks.

When she was in the NICU, she tracked a line between the 10th and the 25th percentile, went up to the 50th after her return home, and my GP thinks she' probably just slowing back down after some catch-up growth.

I'm not sure about this, as one kg in three months seems to me to be really rather little. I'm worried and having a massive crisis of confidence about breastfeeding. Is she not getting enough milk? She probably has 8-10 feeds a day, including about 3 at night. We've been going down the pureed veg and baby rice route for weaning (she's probably having about two teaspoonsful a day at the moment), but should I be aiming for something more calorific in the future?

I'm feeling a bit low and would appreciate any advice or reassurance!

Have you been discharged from the hospital services normally it's a year before you stop seeing the nicu doctors.
I'd ask to see them and not your go.

Thanks for your reply jesy. We've kind of fallen between the cracks in that regard by virtue of having moved countries between the birth and now . We've been referred to a paediatrician (for general follow-up rather than weight gain issues) and we'll be seeing him next week, so I'll try and get the low-down then.

I guess I'm just trying to get a feel for how common and worrying-or-not this sort of low-ish weight gain is. I woke up feeling super-depressed about the whole thing in the middle of the night last night. I was so happy to be breastfeeding her, and now I'm wondering whether it wasn't the optimal way to be feeding her in the circumstances . I've slowly been recovering from ptsd-type anxiety related to feeding dd (after choking incidents in the NICU and feeding issues when we first got home) and this feels like a major setback.