A few days ago i bought these caffeine tablets from CVS. I tried one but did not really feel anything so the next day i took 2 in the mourning 2 in the afternoon and 1 before i went to the gym. I did not relize how much caffiene that really was but did not think much of it. Around 2:30 when i got out of school i felt a little more energized so i thought it was finally kicking in. I went to a friends house where a bunch of my friends where smoking marijuana, i joined them and about a few minutes later my vision started to get very weird. I didnt know it it was just because i was very high or something else was wrong. After about 2 minutes of my vision going very blury and almost making everything around me red, my thoughts started to race in my head. I did not know what was going on. I got up from the table and procceded to walk to my car. As i came to my friends backyard gate i stumbled and grabbed onto the gate to keep balance, i then blacked out for a few seconds and my friend was asking what was wrong then i remeber falling back and going unconcious for about 10 seconds. My friend told me i was on the ground shaking very violent but i got up on my own. After that happend i wasnt sure if it was a seizure or something else, ive never had a seizure before in my life. Im not sure if it was the overdose of caffeine or the marijauna that caused me to have a seizure please give me your thoughts on my experiance, i would really appreciate it.