Miscarriage ??

Jessica 😻
I hadn't had my period since 5th of July until Midday Yesterday. It didn't start with spotting I just started to bleed very heavy midday, Today I am having the worst pains in my lower tummy, thighs, lower back I have ever had. I'm changing my Tampon nearly every 30mins because it's that heavy and so uncomfortable. I am irregular due to PCOS but I haven't been that irregular before or have I had very heavy periods. Is this normal?? 
Might it be because I missed one ?? 
Or i got told it could be a Miscarriage?