You have to pass a set number of credits in order to get a degree - 360 for an Honours degree. If you fail a module on resit, retake or resubmission (depending on your uni's regs and how badly you've failed it) then you will have passed fewer than 360 credits and may be offered an Ordinary rather than Honours degree. Very much depends on your uni though. Resits are usually capped at a pass mark of 40% unless you have Extenuating Circumstances, so yes, they can affect your final grade. However if it's just one module then you're cushioned against it having a radical impact on your final mark.
In all honesty, I'd be very surprised if you've failed the module. Try to wait and see what your results come back as, rather than inagining the worst. We're only a few weeks into the academic year - getting badly discouraged now, might be a self-fulfilling prophesy.