In addition to clomid, there's femara (which is similar to clomid...pills you'd take on CD 3-7 or so), and then of course there are injectables, which are much stronger than clomid and femara. Those all help the follicles grow, and that can often help with a short luteal phase, as well, because it usually leads to higher progesterone levels after O. However, you could also ask for a progesterone supplement to take after O has been confirmed to lengthen the luteal phase.
Is there an RE in your area? If so, I would suggest seeing and RE instead of an ob/gyn. In addition to monitoring your cycles and prescribing more potent fertility drugs (obgyn somtimes prescribe clomid, but never injectables...as far as I know), the RE can also run some tests and make sure everything is OK with both you and your DH.
Best of luck!
Do you have pcos, they gave me metformin for the pcos and i am ovulating earlier and earlier each cycle.