Do you mean the vicodin Trig? if you take them regularly enough, daily etc. then if its in a dose low enough that can cause the beginnings of, but not full-blown opioid withdrawal, then overheating can be one of the first symptoms, along with lachrymation (tearing, watering of the eyes), running nose, generally feeling achey and icky and overloaded, overstimulated. But if your only using them when you really can't bear it otherwise, which from your posts, sounds like its the case, then this is less likely.
If you are willing to tell me the dosage (of the hydrocodone portion of it), and the approximate frequency of use, I should be able to tell you, especially if I know how often, how much and how long the use is for consecutively, doses per day for multiple consecutive days etc. if you are at risk of physical dependence.
I'd suggest you, if you are in as bad a lot of pain as it sounds, renew it, at least the once, so you have them there as a tool available for use, without having to make a doctor appt. suffer in the time it takes between making it, getting the prescription, collecting the prescription, taking a dose and it taking effect, and can go straight to taking and waiting for its onset. If you decide not to use them, fair enough, they won't 'go bad', they'll just sit there, opioids like hydrocodone are pretty stable to storage, the esters are the least stable kind, as ester linkages are easily hydrolyzed, but even then, I've read of people who've found bottles of brand name heroin tablets (the diacetyl ester of morphine's 3- and 6- position phenolic -OH groups), and that were so old they harked back from the days it was marketed as a nonaddictive substitute for morphine by Bayer, and one could just walk into a pharmacy, ask for some, and walk out without so much as an eyelid raised, just so long as one actually paid for the merchandise in question rather than burglarizing the pharmacy, the individual who found this bottle, with its dark glass and yellowing, flaking label reported that when he opened the bottle there was a slight odor of acetic acid from some ester hydrolysis, but that when placed in a spoon, a little water added and drawn through a filter, prepared for intravenous injection, that even the labile ester types can survive an awful, awful long time, and that when administered they were every bit as active as one would expect pharmaceutical grade diamorphine to be.
I'm guess I'm trying to say, Trig, that I'm of the school of thought that it is better to possess a tool capable of dealing with a task that is highly likely to require to be performed, and not need or choose to use it, than require the tool for the task and not have it available.
Better to have, and never need, than to need and never have.