Please can you recall me this poem that begins with, when things go wrong,as they sometimes will. When the road you are trudging seem all uphill?

Sure! The poem you are referring to is "Don't Quit" by an unknown author. Here is the full poem:

When things go wrong, as they sometimes will,
When the road you're trudging seems all uphill,
When the funds are low and the debts are high,
And you want to smile, but you have to sigh,
When care is pressing you down a bit,
Rest, if you must, but don't you quit.

Life is queer with its twists and turns,
As every one of us sometimes learns,
And many a failure turns about,
When he might have won had he stuck it out;
Don't give up though the pace seems slow—
You may succeed with another blow.

Success is failure turned inside out—
The silver tint of the clouds of doubt,
And you never can tell how close you are,
It may be near when it seems so far;
So stick to the fight when you're hardest hit—
It's when things seem worst that you mustn't quit.