Hi, Angelia -
Side effects of IMRT are, as you can imagine, different for everyone. For me, it took almost three weeks of tx to develop sores that were very painful and for which I needed a good amount of pain meds. They also gave me three days off to recover a little before resuming the last three weeks of tx. The last three weeks were harder than the first because I already had the sores, and by the end I was again using a lot of pain meds to manage. The two weeks after treatment were the hardest in terms of pain/sores, but meds did help a lot, as did the constant support of my fiance and family! I also walked a mile or two daily throughout treatment (stopped during the two weeks after; too tired). That's the other side effect that took me by surprise -- the fatigue. It kicked in AFTER treatment, and still has me tiring early in the day 7 weeks post-treatment; I'm trying to be patient with recovery from that, though it's hard.
One more side effect -- the taste buds. Mine have changed so that sweet foods no longer taste good and many things have a metallic/sweet tinge to them. It's not awful, just annoying. And I'm sad to have lost chocolate as my favorite daily indulgence -- it just doesn't taste good any more...
You may have an easier time than I did or a harder time -- it really varies from person to person. IMRT is the best you can get -- much improved from years ago when radiation was less accurately directed at the target area. You'll get to know your technicians, you'll fall into the routine, and you'll even get more comfortable with your mask as you go through the tx.
One other thing to know is that you should eat and enjoy all yor favorite foods now, before you start! Treat yourself to the best, and eat eat eat!
Many people here have had the cisplatin (I did not) and will be able to tell you about the side effects of that.
Good luck with everything! You're embarking on an important journey -- I hope it goes well for you! We will all be thinking of you as you go through your treatments.