Ever heard of this phrase, "Time and tide wait for no man"?

Sometimes when people make me wait for them, i will tell them 'Time wait for no man'. Can't remember exactly where and when i learnt of this phrase. It could be when i was in Secondary School during Literature class. All these years, this phrase has always been in my mind, that's was why i will use it occasionally.
The meaning of this phrase as per the search on the web says, "No one is so powerful that they can stop the march of time". Time passes by so fast that it will not wait.

I am always thinking why time passes so fast, especially when one still yet to achieve what he/she wants. Thinking back, there is always some feeling of regret to a particular thing. If only i have...if only...there are simply too many 'if only". The outcome is not visible but if i try, the situation could be different or maybe still the same??? BUT...as what i had read and heard of, at least once you try, no matter what the outcome is, there will be no regret. Is it true???

I am disheartened...but can't bear to give up.