Helloooo and welcome to you Sue
You could have been describing me!  I am 50 and have been taking HRT for just over 2 years.  The hot sweats seemed to be the first thing to get under control - within a matter of days/a week.  The other bits take longer unfortunately.  They do suggest taking each different type for 3 months so it gives it a chance to work (or not) so if its not too onerous, keep with it?  I started on Elleste Duet 1mg and then last autumn went to 2mg as the night sweats were returning along with anxiety (although I put it down to my job at the time).  The brain fog seems to come occasionally when I am tired or stressed but other times is not a problem at all.  I also take AD's to help with the anxiety.  I have never really day hot flushes in the day, only in middle of the night so I guess I have been lucky from that viewpoint.
Unfortunately they don't call it the change for nothing - it IS a huge change to the body, the mind, the psyche - am not sure what I would have done without this forum.  Even though I don't post as often as some, just reading other peoples issues and responses helps a great deal.
If you can bear it, give it a bit longer and then see your GP if its not improving at all - but good luck, you're in safe hands here ...
SP x