Quote Originally Posted by Andy699 View Post
but the Dr said it's hard to OD on Quetiapine anyway,
He's right. Serious injury, or death is rare even at doses in the thousands of milligram. Most people just sleep it off (it is also a fairly potent sedating antihistamine).

my blood pressure, pulse, ECG and blood results were all normal
The most common cardiovascular effects at very high doses is a drop in blood pressure and tachycardia (rapid pulse). Neither occurred in your case which suggests the dose wasn't that high. The safe dose range for reasonably healthy adults is 50-800mg/day. Am I right in thinking the combined dose was still at the lower end of the range?

However last night I kept having nightmares and I kept waking up with my heart POUNDING, like literally so hard and noticeable and I've had it all day today and now I'm SERIOUSLY scared that I've permanently damaged my heart in someway by taking too much?!
The tests they did in hospital don't support your fear. There was apparently no drop in BP, no tachycardia and no markers of muscle damage in the blood tests. The more likely explanation is the nightmares triggered the rapid pulse which fed into your fears about last Saturday with the resulting adrenaline surges maintaining the rapid pulse throughout the day.