I'm 18 years old and I've been having severe lightheadedness and dizziness for around 4 months or so. When I stand up, I will either feel slightly dizzy for a few seconds or my vision will start to go black like I'm about to pass out. I've been having the almost fainting experience a lot more and a few days ago it actually was the worst. I stood up to reach for something and my vision started to go black again so I just stood there like I usually to waiting for it to go away and I held on to my radiator. However, it wasn't going away and my ears felt full, I couldn't see anything and I felt weak. I knew I was going to pass out so I closed my eyes because I was so scared and the next thing I remember is being on my knees and my head was on them. Shortly after I began to shake and feel really weak, it took me a couple minutes to stand up and my knees were numb. An hour later I recovered completely, but I went to the doctors and he told me it's PROBABLY my weight as I'm quite petite. I am 5"5 and I weigh around 8.5/9 stone. I am helpless! I also have been diagnosed with mild hearing loss, but the cause still unknown. Please help!