New primary or ulcer after radiation?

I'm new to this site.  I am a 57 year old male, diagnosed with SCC (P16 related) on right base of tongue and a couple of lymph nodes on right side of neck.  Never did hear any staging information; they only said it was good that we caught it early.  My first indication was feeling a very small lump while taking my carotid pulse while exercising.  Was treated at Moffitt in Tampa with 6 weeks of radiation (35 total sessions), and six sessions of chemo (cisplatin) in May and June of this year. Due to my 20 years in the military, I turned off my emotions and became almost robotic during treatment.  My last treatment was 27 June, and since then the emotions have been turned back on, and I find that fear (of recurrence) and anxiety about the future have come full force and are nearly debilitating.  I had my first post treatment PET scan on 26 September, and it was clear.  I would appreciate hearing from others regarding how to deal with the fear and anxiety issues as it really is impacting my life.  The biggest issue I seem to be facing lately is contantly worrying about it coming back.  Every feeling or sensation, or even not recovering as quickly as I thought I would is troublesome. Thanks in advance.