How to manage too small paddock?

We will get a milking sheep. Our paddock can't be really called paddock, because it's only 350 m2 (350 m² = 3767.368 ft²).
I want to subdivide it into two mini paddocks, that one part can recover.
But both paddocks will be over fertilized. We have our chickens there too.
I want to plant some shade trees, which I must protect from the sheep too. Maybe some olives, maybe some fodder trees for the animals.
Should I plant something into the paddock while it's resting?
Some ideas how to manage such a system?
How could I mop up the fertilizer?
I had sheep yet there and I fed tons of stuff I collected outside.

I don't have sheep, but they're part of the masterplan...I've read and been told that they need about an acre (approx 4046 square meters) each, so I imagine you plan to suppliment feed quite a bit. Also, being flock animals, sheep hate being on their own and three is considered the minimum.
I've been looking at  paddock-shift/rotational grazing, biological farming and holistic management systems, which make complete sense of course. They're designed for large properties, but could work on a tiny scale.
I think you're right to be concerned about the potentially toxic concentrations of nutrients, especially as you plan to have two species with really high-nitrogen manure.
I have no experience with this, but presuming the chooks and sheep  will be pastured together, I wonder about how chook manure on fresh pasture will affect grazing?
I'm sure someone will come along with some useful advice, I have no answers just  more questions!

Thanks for the answer.
A sheep per acre is IMO a good figure, because of the winter. But I bring tons of feed from outside (maybe not tons armloads). It consists mainly in environmental weeds and everyone is happy that I cut them.
That means work, but you can feed a sheep on a small piece of land if you have feed from outside.
Did anyone keep sheep on such a small space? What happened to the land?