1) Would it be permissible to participate in Quran lessons while people come to know that we maybe have been negligent about learning and our prayers maybe was/is not totally correct?

2) Would it be permissible to tell that we have difficulty pronouncing because of medical side effects or would it be complaining about ones hardships?

1) There is no shame in learning. Yes it is permissible.
2) It is also permissible to share ones challenges without the intention of complaining