Look at this page to find out how to apply for emergency housing from DHCD: https://www.masslegalhelp.org/income-benefits/emergency-assistance-shelter/apply

Reach out to their hotline: 866-584-0653.

Here a mass.gov with more information on this program: https://www.mass.gov/emergency-housing-assistance-programs

It’s a program specifically meant for very low income, pregnant women or those with children that are escaping situation, such as yours, like domestic violence, or sleeping in a car.

Two things,

First, Since you are a British citizen and I’m assuming by extension you son is as well, I would call the British Consulate in Boston and ask for consular assistance. If they don’t pick up the phone because it’s a weekend, leave a brief voicemail explaining your situation, and they will have someone get back to you I imagine. Their phone number is: +1 617 245 4500

The consulate can help provide you a list of resources, and advocate on your behalf to US/Mass government agencies.

Second, where were you last registered to vote/where did you last get mail?

Wherever that is, call your state representative or state Senator, lots them even have their personal cell phone numbers on their website. If not, send them an email letting them know about your situation. they have people specifically dedicated to helping people out with constituent services. They will help you reach out to state agencies, and advocate on your behalf. They have contacts at the various state agencies. If you need to find out who your state representative or state senator is, here is the link from the Massachusetts legislature: https://malegislature.gov/Search/FindMyLegislator