Sick leave when pregnant advice

I’m due 5th March , I’ll be having a c section and that means the week before ( usually, date to be confirmed) . I started this new job in September and had to tell them in my first week I was pregnant ( week 13) so they could prep the risk assessments ( it’s stated in my terms and conditions) , the work is a little physical and involves driving My work were not supportive at all in making adjustments to long distances of driving I did and long hours. It went on for 7 weeks. In the end I asked my union’s solicitor to step in, they wrote a letter pointing out the law and then they did listen. I was REALLY disappointed that I wasn’t important enough to be listened to, I had been telling them for weeks and liaising with the solicitor involved long emails collating evidence - more to do in the evenings. I was sooo run down at that point. I then had a virus, cold sores, bad cold etc. I carried on at work because on the surface I looked ok, it was a new job and by now they had made adjustments. Because of that stress its merged into a chest infection/ mild pneumonia- I’m signed off sick - it’s a 10 day sign off initially but I don’t think I’ll be recovered and will need more time . My question is does anyone have experience of sick notes when pregnant - as in, will I still get my usual monthly wage and for how long? I’m not planning on being off more than I need to, I just want to be armed with the knowledge. If not pregnant I believe a month is the max you can be off work ( with sick note confirmation) and after that your pay is affected. Does this change when pregnant? When I had my organisations Occupational Health assessment( which they didn’t listen to) she told me all the rules are out the window when pregnant…. i.e Sick days you’ve taken whilst pregnant don’t affect your overall sick days when you return to work. I’m wondering here, mostly about pay ..