Afternoon all, - welcome TheBarnes, - sorry to hear you are going through a rough time, and it must be very hard with a rare form of cancer, when you don't have anyone to compare notes with. But stick around - lots of us have been through chemo and we have ladies on here with various types of cancer not just BC, so we may well be able to share some tips 
As for chemo being cumulative - I found that it was, in that I felt more exhausted and my WBC dropped lower each cycle. But I also found that I didn't necessarily have the same side effects each time (although some things stayed constant), but if you do get a particularly nasty SE one time, you won't necessarily get it every cycle.
I also went very pale - with big dark panda circles round my eyes. - V attractive (but made a change from the times when the drug I was on made me go very red and flushed 
)
I also had stomach and more especially bowel problems on chemo - I think it just really goes for anything with a mucous membrane, I hope they can give you something to help - there is usually something they can find, but sometimes they need a bit of nagging and persistence on your part - as I daresay you already know!
Anyway welcome to the thread and many good wishes for your treatment.
Sometimes - sorry you are feeling a bit down, I often get days when I don't seem to get much done, - and oddly its usually the days when I have lots of spare time, so could get on with things. When I'm busy, I get more of everything done. Glad you had a good time at Michael McIntyre - I like him
Smee - great that DS enjoyed judo Its freezing here too, so I have a big cardi on - but every so often I get a surprise flush so I have to rip it off dramatically!
OTM - have a nice relaxing day watching West Wing (brilliant series) you are absolutely right in your approach - I found that you just have to accept the fatigue and feeling awful days and take things easy, - if you try to do stuff you end up frustrated exhausted and miserable. Its very hard if you are normally a busy energetic person, but you can't fight what your body is telling you.
MAS - I think you are very sensible telling your mum, and I am sure she will cope well and be a support for you. We didn't tell DD immediately when I was ill (she was doing her A levels and I didn't want her to worry about me) but in retrospect it was a mistake, - she guessed something was up, and ever since she has always been very edgy when I go to the GP or hospital -wants to know exactly what is going on, because I think she always feels we might be keeping something from her. And I think she felt excluded when she wanted to support me.
love to all - sorry for long post. Taking advantage of my computer being co operative for once (although it is making a noise like Concorde - but that's normal)