Please calm yourself down.
At 14, you are obviously too young to handle a pregnancy
, let alone a twin pregnancy.
Also, even if you decide to go for an abortion
, you need professional help at 14 weeks.
If you decide to continue, you obviously should take the help of your family, counsellor etc.
Please confide in your parents at the earliest, and take the decision ahead with a cool head and calm mind and with family support.
There is no point keeping it to yourself, as you cannot do it for long, and you also need proper care if you continue the pregnancy.
Take care dear.