First time seizure

Hello, I'm new to this site and am just asking for some insight/thoughts on my situation: So on Christmas eve (2017) I was bringing some presents out to my dad's car and as I was bringing the last present out, I asked my roommate for help since it was a 75lb+ smoker and just an awkward box, as I was walking it out my dad had asked, "what is that a port-a-potty?" (Trying to make a witty joke)... Then I apparently put the present down and stared up into the sky for a few seconds, then fell over and started having a tonic clinic seizure for about 3-5 minutes. My dad of course called 911 and had my roommate get a pillow for my head. Then I sat up and was completely mute for a few minutes, then I "woke up" to the fire truck pulling up and paramedics running up to me. I was beyond confused, but was completely cooperative with the paramedics except when they asked if I wanted to go to the hospital and I responded by saying, " no, would I need to go to the hospital?" (Obviously I was still dazed and confused) then my dad said, " you just had a seizure I'm pretty sure you need to go to the hospital." So I did. Then they brought me to the er after the ambulance ride, and they gave me keppra through IV. The had me do xrays and a ct scan. Which turned up clean. I spent about 3 hours there then went to my parents house for Christmas eve but wasn't tired at all from the seizure but had muscle soreness and a painful shoulder and back from falling into the concrete stairs. Eventually got more xrays, and saw my someone from my GP's team and she gave me some meds for my pain and had me scheduled for mri and eeg. I got my MRI this past wednesday and it turned out normal, and have my EEG this upcoming Wednesday. Then nuerology consult the following Wednesday. I am a 21yo male with no family history of epilepsy, besides a great uncle with epilepsy due to brain damage. I have undiagnosed anxiety but being treated with ssri's, and a stutter do to a childhood development disorder called dyspraxia. I had no "aura" before the seizure and haven't had a seizure since. My medications are: (Recrational pot legal in wa) Sertraline Benadryl (as a sleep aid) Vitamin d3 since I work night shift and don't get enough Sun And since the seizure these have been added: Keppra Dicoflenac (anti inflammatory) Hydrocodone-acitametaphen Otherwise I am a completely healthy individual who is 155lb and 6ft As of this moment we have no idea why it happened, I know you guys aren't doctors but what do you guys think? Thanks in advance!