25 weeks down with twin babies.. my feet is swollen to the max. My scan report sugar levels and bp everything is normal. But these days i m feeling giddiness very often and hardly able to walk for more than 2 mins. When i stand or try to walk i can feel a sudden throbbing pain in my lower abdomen it's kind of pelvic pain as well accompanied by constant back pain.. is this pain common in 25 weeks or its happening coz of twins?? When should I be worried ?