If you have done well with a lesser amount of time in your baths, there is no reason not to do two sessions in a day. The sauna may be an overkill somewhat, but give it a try and see how you do. If you feel very tired later and stay that way all day....then you know it is not a good combination. Your body will tell you what you can handle and what you can not.
It matters how acidic your lymphatic system is already. If you draw more acids into the system, you will suffer. No need to suffer when you can pace yourself and slowly bring health to your body.