Should I sue Kings Dominion? LONG story but interesting and complex...?

LONG story so warning you... and complicated. I've got medical doents. Well I'll try to make a complicated and long story as short as I can. My joints pop out. Even my feet, thus I'm flat footed. I have severe knee pain, which is chronic. I haven't had a job in 3+ years and eventually had to tell them. I mean 2 hours then I had to leave... they didn't accept ER notes. This is Kings Dominion BTW! So takes me a few weeks to get in contact with anyone. To find out... now... I'm on a good dose of pain meds. I though it was low since it didn't help. So I'm in PAIN! I have back pains too, not just knee.... well since I have joint issues and it's not just knee... So they're like "Well why didn't you tell us before?" Um... they lost my medical form when I went to orientation. I had to fill out another one. And I listed all the thing I could think of then. Now it is complex but Ehlers Danlos Syndrome is the cause. So turns out I need a back to my chair and the manager claims to have said stool. I don't remember this. I remember him saying he'll excuse the absences... oh yea they also lost all but one of my ER notes. I gave one copy to food and beverage and another to first aid. Three notes in total. Anyway, I'm caught leaning on the counter because of my back. I get told total of 4 times, and written up. Here's the thing. When they told me to sit up straight, I told them I had back pains. The higher ups... even the owner of King's Dominion saw me... but all they could say was "Really? Whats wrong?" When I started to explain they just walked away. Like they didn't care. Didn't even look at my medical record... since they wrote me up for it!! So I get sent home early many hour later. I understood and was ok with it. I was going see HR about it. Now this *****, yea *****, tried to argue with me when I tried to explain I had a bad back. Now I have had no insurance so no check ups and I thought it was fixed pretty much. Simple explanation. She said **** like "Well my back hurts too" and was really being rude. REALLY RUDE! So on my way out my co workers asked what happened. I explained and they were shocked that it was for LEANING due to a medical reason. And I was like yea... Donna THE *****! It takes a lot to get me pissed off. So they said I didn't have a claim when I went to HR the next day. And Jacob, the manager of food and beverage said that he didn't have a chair with a back to it. He would have to buy it. He even said "I'M TIRED OF DOCTOR'S NOTES!" When he was asking for them... now he previously stated that he was planning on excusing my absences then in that HR meeting... he happened to be at... He stated he could only find one of my drs notes and he couldn't excuse my absences until he had more. And he also stated that he's done almost as much as he is willing to do for me... does this sound right? I mean I have medical reasons. I even have a drs note. I had to pay 160 to see that dr and they were like "Well is this a new dr? If so, we can't accept this note!" and I explained to them that I'm under a medical coverage under the VCU hospital. Everything there is free but it takes 4 weeks to 6 months or more to see dr. Unless I go to the ER, which they don't accept their notes... So sounds like I'm going to be terminated due to medical absences and they've been giving me the ring around. AND RUDE! I mean I blew up at one of them, not in their face... I was polite to them while they weren't. I've been patient and it sounds like I'm going to get on disability soon anyhow. But I'm pissed at how they treated me! Any thoughts? Any tips? I mean I'm tolerant to pain, if most people had what I have they would be crawling. I've found out recently that 6 pills of lortab is a lot... it gets rid of more like 75% of my pain. 6 pills... which lasts 3 hours! 7.5-500 hydrocodone/apap is the generic. I took two that Saturday and I'm still hurting 3 weeks later... I told them this and they pretty much asked me to hurt myself to work for them. And they really did demand it. I'm on medical leave ATM. Or so I was told... They gave me until Monday, it's Sunday. Monday as of right after the 4th to get the MRI results of my knee, so Monday the 5th I think it was. I called twice and had to leave a message. No clue if they got it... and went up there... but guess what? They, Human Resources, was off that day... It was a Thursday when I was able to make it up there, about a 40-50 min drive. AT LEAST! SO I'm going back to talk to them Monday... the 12th. I couldn't go the 9th due to a hearing for disability. Which, as I kind of hinted earlier, went well. I've got severe leg and back pain plus ADHD. If I have enough Adderall XR, I can keep my cool. But I'm tempted to let it go and just let them know how I feel. With as litt