You have a crummy situation and have my sympathies. Fluid in the lung with CHF is difficult to control. There are several other diuretics available to a physician. Keep in close touch with him/her. There would be no contraindications to taking 1000-2000 mg of crystalline vitamin C, broken up throughout the day, which in addition to the properties of the vitamin, acts as a mild diuretic. The crystalline form may be mixed with juice or food and is well-tolerated. As you know, you have to watch your diet, especially salt intake.
I can sympathize. I have CHF with a very enlarged heart, and fluid buildup is an every day event. I was taking four Lasix and two Spironolactone a day, but it eventually caused muscle cramps in my hands and legs as well as showing kidney failure, so the diuretics have been reduced to two a day. Potassium and Sodium levels, in my opinion, should be monitored every 2 -3 weeks. Beware of the Internet advice, pay attention to your doctor and the blood tests. Too little Potassium is dangerous, too much is deadly.
Until you stabilize, try to sleep sitting up. I have my recliner, it works well and keeps me from feeling like I'm drowning. I have kidney issues which keep me from taking so many diuretics, I'm in sort of a no win situation, but I'm coping, and work with my health professionals, who have a handle on the situation.
I wish I could give you a more positive answer and solution, but suggest you get blood tests every two to three weeks, and work with your doctors.
Keep us informed.