You can rest assured just about everyone on this forum…both stroke survivors and carers…have been through that particular hell and come out the other side…some are still in it 
Hi @Holliebear80 and welcome to the forum.
Now breath! Slow and deep, in through the nose and out through the mouth.
I myself suffered 2 TIA’s (which are mini-strokes) 3 years ago. And I’m pretty sure your mum is going through exactly the same thing as you are right now, so start talking…better out than in 
Yes, she’s not out of the woods, there is always the risk of another stroke. That’s something all stroke survivors have to live with. But if we take care of ourselves, healthy diet, regular exercise and keep taking our medications, it all reduces that risk.
Is your mum on any medications yet? The standard ones are usually Ramipril for blood pressure, Atorvastatin for cholesterol and Clopidogrel for thinning the blood. Has she any follow-up appointments with the stroke team yet, there should be something or they will maybe phone in a few days.
You can find support and information from the Stroke Association Helpline on 03033033100. So it might be worth giving them a ring. They can also help you find local support groups for carers if you think that would be of help.
Also check out the Welcome post some us put together. It covers a lot of what can be expected going forward and some useful links.
One thing you can be thankful for, she came out of it pretty well from what you say. But her brain still has to heal; just because there’s no visible wound doesn’t mean there isn’t one…you just can’t see the wound in her head. She may be experiencing things like brain fog, she might get tired frequently or fatigued, headaches, balance might be slightly off. All these are also covered in the welcome post. And it might also help your mum to let her have a look through to see if there’s anything she recognises or can relate to
I’ve found my time on this forum has helped me to both rationalise and desensitise myself somewhat from those fears. I’m calm about it, don’t even get an odd pang of concern, but we’re all different, unique 
As it’s a bit late in the day for some on here, I’m sure you will get more responses tomorrow.