Sheds and tyres

I am exhausted! Allow me to explain. I am currently building a new shed to replace my old 8 x 12 which was on it;s last elbows. Building is perhaps an exaggeration, installing is probabky the right word, because I've bought one ready made whcih just requires final assembly. Just......HA!
It is a large shed, 20 x 10 which is almost twice the size of a modern sitting room. Not unreasonably, this needs some substantial foundations to sit on. The manufacturer recommends either 75mm of concrete sat on 75mm of hardcore, or 3 x 3 tanilised bearers on 75mm of hardcore, or paving slabs sat on yes, you;ve guessed it 75mm of hardcore.
Well I had none of the above but I did have some railway sleepers and a 1/2 tone of sand. Not enough railway sleepers as it turned out, so I set off to buy some blocks to make up the shortfall. I reckoned about 32 to 36 blocks would do, so I bought a full pallet load of 40 - better to have too many than not enough right?
Now my trailer holds about 22 blocks, so no worries, 2 runs should do it.
About 1/4 of a mile from the builders merchants disaster struck when a tyre blew out on the trailer. The tyres are about 16 years old and do deteriorate with age (about a 7 year life span) so it wasn't entirely unexpected. I rang home on the mobile to get the spare brought out only to find that that wouldn't hold pressure either.
What do you do in this situation? A trailer fully laden with blocks, with a shredded tyre at the roadside? Well of course, you go and steal a neighbours trailer to finsih the job you started.Yes I have sunk tot he levels of petty crime and taken a neighbours trailer without owners consent. Fortunatley he understood my predicament when he returned home and gave retrocpesctive consent, so I won't be sharing the showers with Bubba just yet.
Any hpw, having loaded a trailer with blocks, then unloaded it into another trailer, then unloaded it again, returned for a second (and then a third) load, then unloaded it three times at teh other end, then carried each block around the house to the site, then lifted them again into final position I am really feeling a little muscle stretch in my arms.
And I still have to build the shed - and sort out the trailer tyres.
I just read the instructions for the shed whch say - 2 man assembly, 3 to 4 hours. My arse!