That variety really should have fruit on by now to be sure to get it to full maturity but that 1 flower may do it if you get a male one quickly.
n I think it is hungry.I would give the plant a feed, aged manure as a mulch, a handful of organic all purpose around the base or a good spray of seaweed foliar spray.
Just check the stem to make sure there is no break in it, I don't think so as I would expect it to go limp rather than yellow but take alook to be sure.
XX Jeannine