Always so tired

Today for example I have got up at 7.30, cleaned the fridge, vacuumed the house, watered garden with bath water (!), made breakfast and washed up, put on some washing and I already feel tired! I’m 71. I plan to go swimming later and will swim for an hour. I don’t sleep well, but surely feeling so wiped out isn’t normal? I’ve had bloods taken and all well in that area, so not anaemic