Iron supplements

Are there any alternatives to ferrous fumarate and ferrous sulfate?

I tried to get an infusion due to previous intolerance to tablets but they've refused so they gave me fumarate, then now sulfate.

but i just cant tolerate the tablets regardless of how I take them, I feel sick, bloated, with diarrhea/constipation and it ruins my appetite. im miserable!

im tempted to just not take anything but im dizzy, have palpitations, get breathless, have insomnia and restless legs and feel faint when stood up for longer than 60 seconds.