Hi liz! I'm originally from Cleveland Moved to SC 6 years ago.
When is your 5k? mid september? I wouldn't wait if it were me.. the carb flu is different in everyone, from what I can tell... for me it only lasted about a week. If you really focus on high fat during the transition and don't worry about restricting lots of good animal fats, butter or olive oil for eggs, salads, etc, and maybe use coconut milk (I make ice cream with coconut milk mixed w/strawberries and freeze!) then I think your transition will go easier. When I transitioned, I ate lots of pepperoni, walnuts and cheese at night and in the afternoon to help me ease the anger of my cravings.. and then after a couple weeks my hunger (and crankiness) subsided and I didn't really need the snacks as a crutch and was able to move more to a paleo diet of meats, fruit and veg, with a little dairy in the morning. Not to mention, IMO there' s no need to move immediately to a super low carb diet! Just transition (especially if you're running) to under 100 grams of carbs, and then after a week lower, or something. Again just my opinion!
Yes, the CW tells us all these things and it's hard to get past it but it's fun discovering how wrong they all are