I drink 4 coffees a day. Minimum. Do get headaches and cramps if I overdo it or dont drink the 2qt of water a day.
Caffeine is a diuretic(makes you pee), which influences the electrolyte balance in the body and your heart's something or another.
Can up your blood pressure. Lots of soda can further throw out the electrolytes, so maybe lower/swap that.
Try and combine coffee with milk or cream to lower the diuretic effect and make the whole thing healthier.
Coffee has antioxidants and can help with loosing weight, energy, lowers risk of some deceases ect. , so not a bad drink.