My work is a joke...

So I am 5 weeks pregnant and go to work as a server right after I get out of my clinicals at a convalescent home for 8 hours... I am having bad back pain, I am super tired and just couldnt do work today I called them and told them I was having cramps and was really not feeling well and all they said was are you sure you cant just try to come in and see how you feel and then they would send me home... Let me just add I have anxiety about going to work in general because 2 weeks ago I slipped and fell and all my manager said was oh we always fall right there you will be fine... Now they arent taking my pregnancy serious by not accomodating me. Also she added well if this is the case you will need a doctors note to confirm everything.. like really I am not lying!!!! Try working with the elderly starting at 7 am all day changing diapers, bathing, feeding, turning, etc and then have to go be on your feet all night until 11 pm... I have had a miscarriage before and dont want to have another... I am sure some of you ladies have it way worse but I am just venting... I would be so pissed if I started bleeding while at work because I slipt and fell or because I am lacking sleep, or am stressed!!!