Hi There,
This sounds quite distressing and it is never easy when these things happen, have you tried contacting your housing office and say you are homeless and pregnant? they can put you in a temporary accommodation. Alternatively you can contact Citizen Advice Bureau for advice for being homeless and pregnant, or Shelter is another good organisation that could help to give you advice.
My advice is to approach you local housing office and tell them that you are homeless and need to be housed, don’t panic you can do this, there is always help you just have to find it. When in doubt google organisations to help support you there a few out there no matter what area in the UK you live in.
Hope this helps,
Stay strong, and take one day at a time.