was my gmail hacked?

Weird one for you guys woke up this morning to my iphone telling me i had the wrong email password for my gmail account so grabbed my macbook pro and same thing wouldn't let me log on so i immediately reset my password via the 6 digit gmail text and within ten seconds was back into my account. Now heres where it gets weird i went into the activity log and the only isp addresses showing are my home and mobile for my iphone so anyone got a clue what on earth happened?