I Take Several Medication Daily. I Had Recently Had To

I take several medication daily. I had recently had to go about 1 week without all my meds. I have recently restarted all of them now and have been on them for at least 5 days. I haven't had any known dental condition ad I would consider my dental health in good health. Until 1.5 nights ago awoke to blood covering my teeth and my mouth being very sore. I rinsed my month and then brushed as long as I could handle the pain. I have also have had extreme thirst. Other then that I have felt good. How can I rule this a allergic reaction .
thank you michele