Do you think I should contact a solicitor
... its a such stressful time...
It may help with your stress to think about the worst that could happen - because while the news is not good, it's not that dreadful either.
The worst that can happen is that the railway* take you to court, you are convicted (that is, you plead guilty or are found guilty) and you are sentenced. It's what the sentence might be and what it means that are the important things to look at.
Firstly, the sentence: there are (broadly) two charges that the railway could make against you, one under the railway bye-laws, and the other under the Regulation of Railways Act 1889 (RoRA). If you're convicted under RoRA then in theory you could be sent to prison. But in practice that doesn't happen unless you are a (very) persistent offender or somehow you aggravated the offence (maybe by being physically violent to railway staff). As neither of these seem to be the case, you will not go to prison. Instead you will face a fine - typically of around half your weekly income. There will also be compensation to the train company, prosecution costs and various court costs to pay - these will add up to some hundreds of pounds.
So obviously there will be a hit on your pocket. You will also have what is popularly known as a 'criminal record'. In some circumstances you have to tell people about this. But those circumstances are generally when they have a legitimate right to see if you're trustworthy - maybe because you're starting a new job or volunteering, or looking for insurance. But for most of these purposes, you only have to mention criminal convictions that aren't 'spent' under the Rehabilitation of Offenders Act (RoOA - confusingly, almost the same abbreviation as RoRA). Byelaw convictions are immediately 'spent' - so if RoOA applies you don't need to mention them. RoRA convictions are spent after a year - so you don't have to mention them for very long.
But there are some exceptions where you will have to continue telling people about convictions (and where RoOA isn't the relevant legislation). Some jobs (mainly those involving a great deal of trust - either because you are handling money or you are intimately involved in a client's life (so personal care, medical professions and so on)) are exempt from RoOA. And if a DBS check is involved then an enhanced check may disclose convictions.
But there's always another level of 'but' - and here it is. In my experience, and from what we've seen on this forum, there are very few jobs which are absolutely closed to you if you get a conviction for fare-dodging. Most employers want their staff to be basically honest - but they recognise that everyone makes mistakes from time to time. One conviction from the railways is likely to be seen as a mistake. Several convictions might be seen as making mistakes but not learning from them: having a conviction and trying to hide it (so not telling an employer when they're entitled to know, for example) would be seen as making a bad job worse. That could lose you your job. But in general, people don't lose their jobs just for having one conviction from the railways.
Put shortly, having a conviction is not life- or career-ending. It's expensive, and it's embarrassing. But try not to worry too much or let your stress rise too high. Even if the worst happens, life will go on.
*For regular readers of this list, I don't think we can be certain which TOC is involved. I know Viking1 has told us that the company is GWR, but as I understand it services from Taplow (which they have given as their location) are now operated by TfL. So (in my mind at least) there's some doubt.
(Edited 13/6: aggregated > aggravated. I am not the best proof reader.)