I got married at the age of 28. I got engaged when i was 27. It's just a matter of time. You will only marry the guy who is destined for you and Allah knows may be he is really busy in doing something right now and that's why u r waiting. 27 is nothing. I never let these thoughts bother me , I know people sometimes taunt you and you feel bad but I think the more single years you get in your life the more better you are. ATleast you are thru with ur education , have enjoyed life and are mature enuf to handle the delicate relationship of marriage.
Don't loose hope. It will happen Insha Allah. Just don't waste your precious time and life in waiting for your MR RIGHT to come. Divorced , Widowed and Single women do enjoy their lives , you should never be dependent on an individual for your happiness. Just be happy and hope for the best :)