You overdid it of course. Drink a lot of water, plain water, sip it, don't guzzle it and the nausea will likely subside. Lie on your back too. You're probably dehydrated.
when you are working out since you havent done it in awhile dont max out which is dont over do it i did that one time and the same thing happened to me cuzz im not an athletic person lol soo just pace yourself when working out.
***DONT DO MORE THAN YOU CANT HANDLE***