Testosterone is also made in the adrenal glands; there are some cis women whose bodies over-produce testosterone, so it is possible. Sometimes, the adrenals kick into overdrive immediately after the gonads are removed, too, which is generally temporary.
However, if it's mostly about mood changes, don't forget that estrogen fluctuations (which often do happen when you disrupt your endocrine system and then dump estrogen back into it) can make people have mood swings and grumpiness. You might just have the equivalent of PMS.
Dena, that page is about testosterone converting to estrogen, which does happen and is a concern when "supplementing" with T. It appears to refer to adding T to a system with endogenous estrogen, though. Estrogen CANNOT convert to testosterone, so that particular pathway is moot here.