to worry about discrimination?

[CrazyCatAtHeart]

I never wear any rings to interviews, as I worry this will go against me. I once had an interviewer ask me if I was married, had children, and if I was planning to!

Experience had made me extremely aware that discrimination definitely still happens in the UK.

I am starting a new job soon, and I worry as I am getting married soon and planning to change my name. I fear the prospect of a newly married woman will send alarm bells ringing for them, and result in me failing probation. It's a small company and they are bound to be worried about the effects of maternity leave, even though I'm not planning to start a family right now.

Do I keep quiet about being married, so nothing can be held against me, or am I being stupid?

It's none of their business whether you are married or not and they should not be asking anything about your marital status or whether you have or intend to have children.
I am married and use my maiden name for work and married name in my personal life.
Entirely your choice which you use, and whether you wear a ring or not.

They can get rid of you without reason at any point in the next two years. Apart from a longer notice period, perhaps, passing your probation won't give you any further rights or safety.

Don’t change your name.