Why only 5? Couldn't it be a result of multiple interactions?
One thing I wondered was how it was for long time not possible to measure the weak and strong force/interaction due to measurement limitations. Perhaps, at scale there are unmeasured(able) interactions. Like _____ is to our scale as quantum scale is to ours.
Like a Macro qanta,the maximum scale of all interactions where forces that cause expansion become too weak and no interaction of any kind,not even electromagnetism is strong enough to exceed this incomprehensible scale...and that is the "universe" boundary. Perhaps at this scale gravitation that causes contraction is stronger and at this boundary and starts "pulling" back all matter and energy. What if just like there is strong and weak forces at the subatomic scale, maybe there is similar strong and weak gravitation? Of course I am asking uneducated questions with no background in science.
As each type of force correspond to one type of boson - which mediates the interaction - it is indeed right, in this meaning, to call them also types of interactions.
Also important is the fact that the discovered particle is a fundamental particule, so it is not a composite of other fermions and other bosons. That excludes the possibility of mistaking a mixture of existing forces for a new one.