Sorry to hear that hun. I have them a lot as I'm very prone, just after Easter I had one that didn't respond to the antibiotics they gave me and as it hadn't been treated properly I ended up with a very nasty kidney infection and just escaped being hospitalized. I'm not trying to scare you but PLEASE go to a walk in centre and see a GP asap as you shouldn't wait around if it's not responding to extra water or those sachets within 48 hours. When you go to the Dr make sure they send off a sample to test because they need to find out which bacteria is causing the infection in order to treat it, what they do is they treat blind until they get results. My Dr didn't send one off after Easter and that's why it got bad and traveled upwards as it took them longer to find the right medicine, it has never happened to me before that it has got to my kidneys (and when I was in my early 20s I had 3 or 4 bouts of cystitus a year) because the Dr had always sent off a sample so make sure they do it.
Other tips are:-
(unless you have high blood pressure) a teaspoon of bicarb of soda in water a couple of times a day as it makes your urine alkali which stops the burning
Cranberry juice- as it helps prevent the bacteria from sticking to your urethra and bladder
Paracetamol- for the pain
Peppermint tea- is alkali which helps stop the stinging
Hot water bottle- for any back pain/pain in your sides although these symptoms can indicate kidney pain so watch out for that anyway
Rest in bed or at least with your feet up
Drink more water than you feel possible- my tip is to put some boiled water in a glass of cold so that it's warm as it makes you feel less sick to drink lots of warm water so you can drink more. Think pint glasses full, as much as you can.
Empty your bladder as soon as you need to, don't hold onto it.
Pouring water over your urethra when you pee also soothes it I find, those sports caps on water bottles are good as you can kind of squirt them as you sit on the loo if you see what I mean

, it helps keep that area clean as well but cold water kind of numbs it if you're in a lot of pain
You have my total sympathy hun as it is horrid just please please get it checked out and don't wait any longer as once it gets a hold it can get worse quite quickly. Look out for pain in your sides, bad headaches, feeling like you have no energy, a grey look to your face, a temp and also a very weird shivering thing where you can't get warm as those are signs that it could be affecting your kidneys.
I hope I haven't scared you, I'd just hate you to end up being any sicker as it's awful

Hope you feel better soon
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