it's hard

i'm on my third day of the 2 a day runs - today was better then yesterday. Yesterday as the 2nd run started I crashed and burned. i've had this happen before. 3-4 times over the last 2 plus years i've been running. i don't know what causes it but i just feel weak all over - like i'm about to collapse. it felt that way walking over to the DAHLC. i still got dressed and on a treadmill hoping it might go away - it didn't. the first day of these double runs - Monday - went great and today was good too. For the record yesterday i weighed 245.6 and today 244.6, so it's dropping again. just need to stick with this now.