From last three days, when i stand up from lying down i feel dizziness or sometimes everything go blank for 3-4 seconds. Dizziness remains for less than 1 minute. But when i first sit from lying down and then stand up thn nothing happens. Most of the times my blood pressure remains low and sometimes i am also feel a little bit of pain in my left arm.Is this a serious condition?And please tell what should i intake for hypotension other than coffee and salt.