Thanks for posting your query.
Considering you are pregnant, it is best to go to either ER or your doctor straight away.
Although these are nonspecific of any particular medical condition, it is better to get your doctor check you up. Dizziness
and breathlessness are common in pregnancy
, more so if you have twins. But, it should not be neglected and the doctor should examine you, take your blood pressure and order some relevant blood tests.
Hope that helps.