Go to your social services and apply for medicaid, I would also set up an appointment anyhow so you can see how you are progressing and get prenatals (:
Are you in the US? Go to healthcare.gov, there are instructions there for applying for coverage.
Go to your local d.e.s office. And apply when u go make sure you have proof of pregnancy either from a doctor or go to a free clinic that does pregnancy test.
Health insurance through the state is free (medicaid/medicare) should be approved in one day