my b17 gsr has done this time to time with me too! check the wire leading to the starter , make sure it has a good connection , also could be your starter taking a shit . try to crank it numerous times and then take a break and repeat , if your patient you might get it to start. so you can take it home to better diagnose the problem. but try this before you pay to have it towed.. Like I said this has happened to me before , turned out the wire leading to the starter had a bad connection.