Colleague is getting a higher wage than me - England

I'll try and keep this short and I do apologise if this question gets asked frequently. I'd like some feedback from anyone regarding this TIA! X

I have 13 years of NHS experience (Emergency Department receptionist, dental nurse, call handler, theatre practitioner) and I have just passed probation at my 6 month new job as a Secretary.

I got told before I joined the role my wage would match the other secretary after completing 6 months probation. (The other Secretary was not happy about this btw and was adamant I shouldn't get the same wage).

I found out in my end of probation meeting that my colleague is on more than me due to her experience.

The issue is we work idential job roles and pretty much have identical previous work experience, and she has worked in the secretary role 1 year longer than I have.

I can't help but feel really frustrated about this - her wage isn't a topic of discussion and I haven't been told about possible pay increments the longer I work there.

Any help would be appreciated thank you.