Hi Esther, I'm sorry to hear that you're going through this.
I would be scared and confused too.
Here is a link to the UK Child Support Agency page related to your circumstance.
http://www.csa.gov.uk/newcsaweb/faq/application/abroad.aspNear the bottom, it does state "This is a reciprocal arrangement which means that foreign maintenance orders in favour of individuals abroad can be registered and enforced by UK courts against UK residents. "
And one of the countries it has the agreement with is the USA, though "United States
(not Alabama,
Mississippi,
South Carolina, or
District of Columbia)"
So you'd have to start with your local child support agency or courts. They'd best be able to advise. You can collect if you get an order for support there. Legal aid might be an option.
My husband was in the UK when our oldest daughter was born in the USA (before we were married), I got a paternity form and posted it to him, he had it signed and notarized and sent it back to me to pass on to the Dept of Statistics or whatever it was callled then.
Best of luck to you, I hope it works out, things usually do work out in the end. Drop in on us anytime. ((((hugs))))