My son isn't responding to his ADHD medication?

So my 7-year-old son has always been a bit of a handful. As a single mother I've dealt with it the best I can but recently it's been almost too much for me to deal with.

He's been been acting up worse than ever at home and now it's even begun to affect his schooling. He's currently enrolled in first grade and according to his teacher he's been refusing to participate in his school work, distracting other students with his behavior and even been openly defiant of authority figures.

Our pediatrician refused to prescribe any ADHD medications so I ended up just buying some off a family friend and ordering the rest off the internet.

He's been taking them for two weeks now and so far I'm seeing absolutely NO change in his behavior. If anything he's been getting worse. I had to pick him up from school two days ago after he attempted to bite his teacher when she tried to confiscate his iPhone.

What's my next step here? I feel like I'm beginning to lose control of the situation.

Well the good news is he's not responding to the meds so it may be a misdiagnosis. What type of punishment are you giving him for this behavior? Biting is a big deal!

When medication does not work, IT MIGHT be because the Condition does not exist. False diagnosis. Internet "prescribed" drugs could be placebo, out of date, or wrong strength.

Buying and selling prescribed medication is a State and Federal Crime.
Possession of a prescribed medication by a person other than the original patient is also a Crime. Prescription medication, stored in an unlabeled container is also a crime.

He's not been diagnosed? Your giving a kid legalized speed and you're not sure?
Try another Dr