Big sister needed!

i had sex on the 23rd unprotected and my partner finished inside, i took a plan b around 12hrs later. i was on day 25 of my cycle and my cycles last around 32-45 days so i never know when i ovulate or when my period will come. started spotting on the 25th and it got heavier the next day and turned into a “period”. my periods usually are light and last about 4 days. i’ve been bleeding for nearly a week and it seems to be getting heavier. my question is this my actual period or just plan b bleeding? How well did the plan b work if I had already ovulated? Should I expect another period in a week? i have never taken a plan b before so i need a big sister to educate me!