You took ipill and got a period.as per your assumptions the next period must come on time. But this is wrong
ipill is a high dose pill which can prevent pregnancy but it also causes the normal hormonal pattern to get disturbed.
Hence you may experience delayed or early periods, less or more bleeding in next few months
Next Steps
if you are having sex more than once a month, its best to use condoms or oral contraceptive pills of 21-days