given that history of
diabetes and blood pressure, you have increased chnaces of developing them, but when that can not be predicted in advance, as both of them are multi-factorial , you weight is normal for your height,
you do gym , that helps cardiovascular fitness, but i suggest doing cardio along with your gym, atleast 3 days in a week.
Good life stlyle and healthy diet does reduce chances of you getting DM/HTN.
regarding bubbles, dont worry it does not indicate diabetes.
Diabetes is not diagnosed that way, if you want to confirm you can do fasting sugar ,PPBS and
HBA1c.
your pounds, that can happen due to a extra beat or a missed beat, once in while its acceptable, but if the frequency increases or that becomes rapid pounding persisting for significant time duration , you need medical attention.
Said this if pounding is once in while , lasting for hardly one second then you should not worry.
as you have history , i suggest you do atleast yearly health examination once you turn 35.
If you want to ensure your and assess your cardiovascular fitness then you should (but not necessary at all) a
stress test also called TMT/CST and see how many METS you achieve on that, and repeat yearly and keep log of METS of every year. it will help to assess increament or decrement in your fitness over a period of time.
hope this helps you