It can be quite challenging to look at your own performance and ask  whether or not is was any good.
Many students can be quite harsh on themselves and demonstrate unrealistic expectations.
Others have the impression that they are already skilled  and are looking for confirmation of this.
Recognise that are no doubt making countless  mistakes.
Accept this.
It is OK.
Even if the instructor were to offer a list of  corrections, you may not yet be capable of  addressing the points listed.
This is to be expected.
Understanding takes time.
Go easy on yourself.
You need to look at your performance in simple terms. 
Note obvious errors. 
Correct these as well  as you can.
There is no need to be judgemental or overly  critical.
You are where you are.
You are only as good as you are.
 
 
