@Cornishcornettos, just wanted to send more hugs your way and to add my bit that it's completely normal for Freshers to begin feeling overwhelmed and just wanting to extract themselves at this point in term. For some degree subjects - not all - the workload is ridiculously demanding and doesn't sit well with someone who's always, before, been able to keep on top of everything and meet their own high expectations. I do think a lot of it is to do with starting to aim for 'good enough' rather than perfection. Another thing for your DS to think about is, what's his eventual aim, post uni - and why did he choose this degree? Then working backwards from this, he can decide if it's worth pursuing and getting over this hurdle with any help and support available or changing tack.
Although my DCs seems to be thriving, I didn't when I was at O forty years ago. I seriously considered changing to a subject that matched my A levels and where my strengths lay, rather than a completely new path, far away from my natural abilities. However, I had an end goal career in mind and so stuck it out and by the second year, was managing much better. My degree was one that had lots of component parts each week, not just one or two essays and I think any degree that means juggling lectures, essays, worksheets, labs etc etc is far more demanding than those where you just focus down on your topic or topics for the week and write essays. I don't regret staying the course but I do sometimes wonder what would have happened if I'd swapped to English or History - which are in fact the degrees my DCs are studying and ones which I'd have found much easier.
If your DS can talk at length to his tutor and to second years and perhaps wait until he's recuperated a bit across the vacation before making any major decisions, then he may gain more perspective. Right now, I doubt he's in the best frame of mind to make a decision.
@Beeswain, just wanted to say it's lovely to hear your DS is enjoying life at uni now and playing a lot of chess. This sounds great and given he's done so well academically, he probably knows best where his interests lie and if he wants to add Statistics to the mix, this is probably right for him!