Never Ending Period

Lillian
I know it's normal for a 17 going on 18 year old girl to have her period, it's kinda a no brainer. Mine usually last 4-5 days (including the minimum spotting at the end) but starting in July I've noticed that my period had lasted a little over 7 days. I didn't think nothing of it until come the end of August and I had my period for roughly 10-12 days. But it doesn't stop there, less than a week later in September my period came back again! It has been 3 weeks since my period gave me a surprise visit earlier this month, 5 weeks including when I started in August. Before you ask, yes I did talk to my mother about it, but her response was simply asking me if I want to gain more weight from birth control. I'm over weight and birth control is a major phobia in "my" aka "mother's" world. I'm seeking any advice on what I should do cause I'm so sick and tired of bleeding out, to the point where I'm surprised I'm not passing out from blood loss(note sarcasm). 🙏🏻