Inception, my dear friend, your solution should be just fine. Refilter for an additional course if you are nervous with the solution being cold, but not freezing. I understand that you have anxiety, but I fully trust in your skills to pull this off time and time again. You've don so in the past so have no fear.
For the record, there are some very obvious indicators of APAP overdose like intense, excessive vomiting. Not the "haha, look at that, I threw up!". kind of vomiting, the other kind; painful retching and complete emptying of the stomach leading to further excessive painful vomiting with the intensity of pre-natal contractions. I've done it.
You're fine. I take full responsibility for your life and stand by what I have said. Refilter, rechill, with powder fully submerged. You will be fine. You're a smart guy and you're just paranoid. Granted, it's a very healthy, primal worry of death that will serve you well through your time, but in this instance, you're good.