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.