In fact (why don't the docs prepare us for this, grumble, grumble), it's very common for the first few months after a hyst to be a time of hormonal fluctuations. This is when we are gradually using up the stores we had from when our ovaries were in production. No matter what estrogen and what route we use, it's not likely that the first dose we take postop will be our final long term choice.
For many women, then, the first post-op dose is either too large or too small (or, over time, both). Migraines are a classic for estrogen excess or estrogen inadequately balanced by progesterone. Breast cyst stimulation and general breast swelling are also often a result of high esterogen relative to progesterone. The fact that when you stopped the estrogen supplementation these things resolved would also reinforce that interpretation.
As you are guessing, your body may not need more estrogen at the moment. This will probably change over time. There are some women who do not need ovaries to maintain adequate estrogen levels. The adrenal glands are able to convert some other substances to hormones, your belly fat can produce a weak estrogen in specialized fat cells, and we get a certain number of estrogenic compounds (referred to generally as "xenoestrogens" ) in our diet (eat a lot of soy?--that's a common one--but there are also estrogens in commercially-raised meats, for example) and from the environment (plastic and some pesticides are also estrogenic). Women without ovaries who can truly provide for all of their hormones needs via these sources are, I believe, relatively rare but they do exist.
So your situation may persist or you may find that over the next few months you slowly note the onset of moodiness, hot flashes, vaginal dryness, and other menopausal symptoms. If not, then you maybe should just monitor your bone density and continue annual checkups and count yourself in the no-hrt crowd. If you do develop these symptoms, then--only then--it's time to revisit hrt.
When/if you find yourself reopening the hrt question, I'd suggest that you spend some time researching hrt options and in particular, the role of progesterone in balancing estrogen (yes, even in hysterectomized women). Progesterone is believed by many practitioners to be a required adjunct to estrogen in women who have had endometriosis, in order to prevent estrogen from stimulating regrowth of any microscopic remnants of endo that may be left after surgery. Some practitioners, in fact, put post-hyst endo sufferers on progesterone-alone for a certain period before they begin estrogen, just to be certain that any remaining endo is thoroughly supressed. This is something, I would think, that you might want to look into. Feel free to message me if you need some pointers on where to begin looking.
Remember, even though the doctors tell us that the recovery is 6-8 weeks from this surgery, in fact it takes at least a year for our body to fully heal and work through the various hormonal adjustments. Although I have had a pretty smooth time of it, I did adjust my hrt about 4 times in my first post-hyst year, and have been re-evaluating my doses for the past several months (just to be sure they are the lowest possible effective ones). It's a little more complex than the breezy "oh, you'll be fine after surgery--you'll just have to take this little pill" assurances some doctors offer, but it's well worth working with, for your health for the rest of your life. Good luck with your learning process--