struggling

hello,

I have been on myfitnesspal for around 2 years now. i started off at 300lb, and I got down to 226lb within 6 months through cardio exercise and strict diet. as i lost weight so quickly and was overweight for so long, i opted to have a large tummy tuck with liposuction on my flanks to achieve a good contoured body and shape. the surgery was a success but 7 weeks on i still have a seroma on my stomach where my skin was taken and my flanks are still quite swollen and painful. i had a large overhang of loose skin and fat which would not move regardless of exercise.

the question in hand is, once i came out of surgery, i weighed 218lb. they took 7lb off me in weight total. during my 4 days in hospital i didnt exactly eat very well, and was eating maybe 1000-1500 calories a day.

7 weeks on, i have put on 11lb. I am certain that probably 1-2lb of this weight is from the seroma on my stomach which is going to need draining pretty soon, but 9lb of it, i am not sure where its come from.

I was eating 1500 calories a day before my surgery and maintaining weight which was actually quite worrying as 1500 isnt a lot, i wanted to be losing in reality. after my surgery, i stuck to 1500 calories a day, with a few days here and there where i would eat 2500 or so. following this for 7 weeks, I have put on 9lb. my clothes fit the same and i dont feel like ive put on any weight by looking in the mirror.

my personal trainer wants me to eat 2500 calories a day with all the hypertrophy weight training and cardio i do at the gym, and says 1500 is nowhere near enough and 2500 is the minimum i should eat. i haven't yet adapted my diet to eat 2500 calories a day, but i am training 3-4 times a week doing cardio (HIIT) and heavy weight training and even at 1500 calories a day I am putting on weight. i cant believe it is muscle as i have only been back at the gym for 2 weeks or so, so any muscle gain will be very small.

i am losing motivation and i cant figure out whats going on. my PT says my body is probably in starvation mode by eating so little, but eating more seems like such a step back. all i want to do is get back down to my 100kg goal weight, but it just doesn't seem to be happening. im scared to eat more as i think i am going to put more weight on, so as of today i am starting a 150g of protein a day (shakes) with water, thus making my calorie intake around 550 calories a day, and i want to try this for a week.

please help i definitely do not want to have paid over £10,000 for me to put weight back on!