Your extreme need to stuff yourself with food when you get like that, is the quite natural instinct of the body to try and raise blood sugars as quickly as possible. These cravings are the body surviving! What you descibe sound like quite quick and low drops to me, I would call them severe hypoglycemic reactions. You are at risk. The quickness is expecially concerning for your well being. I understand something is keeping you from a doctor/diagnosis, but make it your top priority. Only a diagnosis and medical help by a doctor will get you out of the danger zone. No one here can say whether you are at risk of going unconscious or not.
What you can do in the meantime.. have a phone nearby at all times. If you are really concerned about passing out and can get to a chemist before your diagnosis, go and ask at a chemist/pharmacist about a glucose injection kit. I don't know the actual name of them, but the one I have seen is a large injection with disolvable glucose and water that can be quickly mixed and injected by someone else in the event you pass out from low blood sugar.
The following is more medical advice than I like to give, but if you really can't get to medical help for some reason, I think they are blood sugar commonsense until you can discuss it with a doctor.
Try and snack on long acting carbohydrates through the day. Wholemeal bread, cereal, fruit, moderate amounts of juice, are all examples of good foods to snack on every few hours. Hopefully this will prevent those crashing lows. Unless having a hypo, avoid quick acting foods like chocolate, sugar, lots of juice, chips, etc, these may cause blood sugar instability as I outline below the reason is down below.
Have food on you at all times. I find juice rather than sweets to be a better, longer pick-me-up, but any simple sugar will do. Have a set amount (say, 15g) of this short acting carbohydrates as soon as you feel faint. No change in 10 minutes, have another. It is much better to head off the worst of a hypo than get to the stage you are in the middle of it.
If you get to a very low state again and feel like eating and drinking excessively, try and stop yourself after you have had a certain amount of carbs. 30 or 40 grams of quick acting carbs should be enough to get over a severe hypo. For example, 300 ml juice max, 3 pieces toast max, a chocolate bar, max. Then try and wait 5 minutes to see if the symptoms allieviate. If not, repeat. These cravings are the body literally surviving and apart from heeding their command to get SOMETHING to eat, they are not accurate as far as telling you when to STOP eating.
Then once you feel better eat a nice portion of complex carbs to keep things going.
The reason you should try and have somewhat controlled amounts of carbs, and avoid quick acting food in the normal course of eating, is that your blood sugar may spike up the other direction and then back down in some hours, a rubber band effect. Whether your condition includes this effect or not I can't say but it is worth avoiding these things in case.