You might! If they are continent to increase in strength and frequency than (depending on your time zone) I'd say your at least very well on your way! Good luck.
How long had it been since they sent you home?
At About 10:30AM It's 1:38PM Now
Try taking a hot bath or even shower. Sometimes the hot water helps to relax your body in a way that progresses labor. Plus the hot water helps with the discomfort (double bonus;). Continue timing them. I even downloaded a contraction timer on my phone to make it easy for me. If they continue over the next hour I would call L&D and go back in to be checked.
My midwife said contractions lasting 3mins writhing 10 mins you should go in. But then it depends on your body