Problem related with pregnancy.

My LMP 23.12.2017, I have strated my pregnancy 59.96kgs,I have normal BP,23.7.2018 i have completed my 7months,but I have gain only 3.3mgs,nw my weight is 63.26kgs.At the end of my 7mnth diagnosed diabetes,where random sugar 128,next day fasting 83,2 hrs pg blood sugar(oral challenge with 75gms glucose,) 178.I can feel the baby movement properly.21.7.2018 baby growth was 30 weeks.I have low lying placenta,lower edge covering the Os.M taking cpink total,c dense, folinal plus and glycomate 500s.r...Nw m worried dt why I gain so less weight? Is my baby growth nd weight is fine? What should I do..? Previously m tkng mother's horlicks,nw I stopped it for diabetes.which protein powder I cn have (sugar free)? And is my diabetes is gestational diabetes? Please help. Thanks in advance