If you did not get my point about that , i can simply say small investment will not gives you anything good as a profit just get another small additional money.
If you okay with that situation , there is no harm right? Just do it.
It is not one is right or bad in investing. Instead of waiting for a bigger amount to start investing. It is always good to start with smaller amount and learn how it works before you increasing your investment on any particular product. Off course small amount means less profit, but one is also taking a lower risk to learn the investment, so I suggest to start with smaller amount and over the time increase your investment amount.