The soda ruined any chance for you to have a good read. Try again another day. your best bet is to try it every few hours until you get your "baseline" down. Have a normal meal tonight, dont do anything tommorrow, and dont eat or drink anything (except water) after 8pm tommorrow night. Take it when you go to bed, 4-8 hours after your last meal. Then again 1/2 an hour after you wake up, but before you eat anything. This is the easiest way to get the no food reading. Eat a normal breakfast, wait 1 hour take the test again, then right before you eat lunch, then an hour after lunch, same for dinner. Do the same routine the following day but test yourself 1/2 hour after you eat. That will give you a baseline to go by, and you can compare numbers for future reference.
Even though the simple sugars in soda pretty much go through your body in no time, if you don't have any simple sugars (soda, coffee with sugar, candy etc...) they will still linger in your body giving you abnormally higher levels for a few days.
124 isn't that bad, slightly high, but I bet it's because of the soda you drank. I bet that without soda your fasting sugar will be in the 110-115 range which is perfectly normal. At 124 that could be just your diet, cut out sugars, like soda, and it will drop super quick.
I test every tuesday morning and I generally see numbers in the 95-110 range depending on what I ate the few days prior. I have also seen numbers as high as 142, which triggered a quick trip and stay in the hospital over night (after which my sugar was back down in the "normal" range).
Like I said 124 isn't bad, just watch what you eat, keep a log of what you eat and your sugar levels if you are really that scared.
***Disclaimer***
Go see a doc and get them to evaluate you. Those home testers are OK, but the cheaper ones can be off 5-10 if they are not calibrated correctly. $70 is pretty cheap for a testing unit. My cheap one cost me $350.
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