it can depend on many things, including the type of orthtotic wheter or not you have had support before, body weight, running style etc etc etc.... but one day after getting them is pushing it a bit, normally i recomend whereing for 2-3 hours day 1 and adding 1-2 hours per day, some people can wear an insert all day after only a couple fo days some take 10-14 days....after you are able to wear them for most of the day then a short run 20-30 minutes should be the first run, then build up slowly, no nor than 10% per week just as though you were building up from not running
all that said, a few years ago i built a set of inserts for a woman at marathon expo (on the saturday) despite being told not to run in them...she ran the marathon then sent me an e mail (i was dreading reading it!!) it said, " thanks for building my inserts at the show on saturday, it was good of you to fit me in at short notice at a busy event.... against your advice i ran the marathon wearing them, i got a PB and to be honest with the niggle i ahve had in my foot for the past 2 weeks i am not sure i would have made it round without them"
a supportive shoe may help you for everyday use, but can you wear running shoes to work??? if the pronation is that severe then you probably should be seeing someone about getting an orthotic insert to help support your foot a bit better
all depends on your biomenchanics but in a lot of cases yes they can, however if you keep getting injuries from a new shoe i would be questioning if it is the correct shoe prior to getting an insole...
it could be that an insole will just add to the shoe and make it function better, but it sound slike you really need to get it checked out