Hi. Has anything like this ever happened before? How long did this episode last?
Do you have any medical conditions?
OK Felicity. It sounds like what's called a vasovagal reaction where the vagus nerve gets stimulated and slows the heart rate and lowers the blood pressure. Same thing happens for example when people nearly faint at the sight of blood. Nothing too serious
That said, however, this could have been a cardiac arrythmia problem and for that reason you need to see a doctor right away for an exam, an ECG, and an echocardiogram
Let me know if you need any more information please.