for most people and compared to other antibiotics doxy is a pretty benign antibiotic
to help give some context -
-its given long term ( years) to many many people for acne - which is not a life threatening condition
-and its given routinely for recreational travel to malaria endemic countries as prophylactic
also - i do not see problems with hearing commonly listed as a prominent side effect of doxy
eg see side effects list here
https://www.rxlist.com/consumer_doxycycline/drugs-condition.htmand the symptoms you are experiencing though in the same area of the body as the side effect you mention - these are obviously not caused by doxy as i understand you are not yet taking it.
they are therefore very likely caused by a separate mechanism, driven by the infection or inflammation.
as a result the doxy may well help these symptoms rather than make them worse - at least its not a safe assumption that it will make them worse.
to my mind the risks and consequences in delaying treatment far outweigh the risks and consequences of increased side effects.
doxy is about
the best antibiotic to use in early stage lyme ( first month or so ) after that combinations - may well be required - but will often still include doxy - along with other modes of treatment - in particular diet and lifestyle changes and herbs can be transformative for many
adverse reactions are possible with any drug - or herb for that matter - and sometime inflammation goes up during treatment before going down - so i would just monitor as you go and be prepared to stop if you do have an adverse reaction and really cannot continue.