still high over 12 hours later? feeling of lead rushing through my veins?

My roommate and I smoked last night, a blunt between the 2 of us at around 12 last night. We're both pretty small girls in our late teens/early twenties. I had a crazy case of the giggles at first but shortly after I had an awful panic attack. My heart was pounding, I was shaking and I keep getting this rushing feeling like lead was flowing through my veins and this weird pressure at the back of my head keeps coming back. I started hallucinating too and my skin looked really splotchy. The thing that really worries me is that I'm STILL experiencing these symptoms!!!!! I feel really off-balance and kind of out of it when i walk. I also keep having that same pressure feeling in the back of my head and the feeling of lead in my veins. Someone please help me I feel like I shouldn't be feeling like this. I'm so so worried something might be seriously wrong with my or my weed was laced. I hardly ever smoke and this was my first time getting REALLY high I don't know what to think or do. Someone PLEASE HELP!!!