I honestly didn't suffer any side effects with the lucrin personally but when I feel flat I generally look at more exercise and sometimes an increase in my iron intake. Definitely not a water issue in my experience
Additionally, the whole IVF process the first time round being a guinea pig is hard work and quite tiring because you always feel unsure or uncertain. So maybe its a little anxiety as well. At least it was for me!!
Hope you start to feel better soon.