So, let me get this straight:
1) You started a Tekkit 3.1.2 server. That's SMP, Survival Multi-player.
2) You launcher Technic 7.2.6 with your client. That's SSP, Survival Single-player.
3) It didn't connect, for some strange reason.
4) You came on this board, and posted in the General Tekkit SMP section, instead of the Tekkit Bug Board.
No, I'm afraid I really can't help you.