Shellyjayne, problems with digestion, IBS etc come up on here all the time so rest assured, it's very common and it is connected to menopause. I had a consultation just over a year ago with a gastroenterologist who explained how hormones/menopause affect the gut.
It's complicated I'm afraid. In my case it was connected to low/poor circulation of serotonin and silent migraines but very often IBS and digestion get worse post menopause. If you search for menopause and digestion you will find a lot of helpful info out there.
Bile acid diarrhoea is also quite common.
I'm 61, 15 years post menopause and using low dose, continuous combined HRT with 50mg amitriptyline (an antidepressant) every day for migraine prevention and it's working very well. Amitriptyline also works well for pain relief, IBS and digestion issues so it's multi pronged medication.
If you are sweating as night you need HRT so I would start with that and then add in further medication if needed. So it's a question of which type of HRT to try and I would say definitely transdermal and preferably Oestrogel.
I hope that helps.