feeling heartbeat difficulty, breathing, epigastric pain when standing after sitting for a while not too long??

[scoop85]

i've been living with diabetes since i was 10 years old, and by the age 18 i've started to feel heart pain problems and and epigastric pain at the same time when i get up from the bed or stand after sitting for a while,sometimes or mostly when i stand after sitting  for a while i feel a pain from my epigastric region and at the same time i feel that my heart beats hardly like it's facing difficulties for beating easily, also difficulty of breathing at the same time and i feel like i should sit back again inorder for this pain to relief,i've always checked my blood suger at the time of this problem and mostly my blood suager is not more than 235 using one touch device, when i get nervous or get into a fight i feel like my heart is going to stop and my face becomes reddened like it's going to explode, my weight is 87 kg and my height is around 170, i do take vitamin b complex via intramuscular part,and i also do take wheat germ oil capsules vitamin e so i need your help and tell me whats my problem with my heart