Is this normal?

My period just ended a little over a day ago. All day yesterday, i had like no discharge nothing. Today i notice i have this medium brown leaky discharge and tmi but it smells a little bit, like old blood but also just like sweet/sour and its gross. This usually always happens after my period for a few days then goes away and then i smell normal with regular discharge. Im just concerned because i was supposed to have sex tonight, thats been planned, and now idk because i dont want to be embarrassed.