High Blood Pressure, Increased Heart Rate, Arms Shaking Severely. What Are The Causes ?

Hi, I've recently found out I have high blood pressure, I'm waiting for a blood test next Friday to check kidneys and cholesterol and sugar metabolism. I had no symptoms regarding the high bp. This Sunday, 3 days ago I was lying in the garden I'd been out there probably half an hour, I had just fallen asleep and I woke up and my heart rate was incredibly fast, I've never known it beat so fast, I couldn't catch my breath, I went inside and had a drink. I breathed into a bag which brought the heart rate down but I lost feeling in my legs, arms were shaking quite severely and I had to sit down. I had a sugary drink as I thought my sugar level may have dropped but this didn't help. I came over incredibly dizzy and felt like I was going to faint. I stayed on the floor and 5 hours later the dizziness eventually calmed down. I went to bed that night but every time I was just about to fall into sleep I went very dizzy like I was being spun round. For the past couple days I've been in a constant state of light headedness and dizzy if I move my head to quickly or look down. The difficulty getting to sleep isn't quite as bad. I was at work yesterday and I stood up and everything went very distant and I saw white flashing dots appear for a good 10 seconds until I sat down. I find it gets better once I eat a meal. I was involved in a small car accident on Thursday where I hit my head on the glass but it was a very very minor accident... I'm not sure whether these symptoms are caused by the bump to my head or something with my bp?