I just want to thank you for all your help, advice and kind words -- a girl I met dog walking put me onto this site and I'm so glad.
This morning we followed David's advice about only giving her her food if we can stroke her and she doesn't growl. She started off growling and was obviously frustrated as she wasn't getting her food on her terms, but she soon got to know that she's not to growl when we stroke her and she gets some of her food - she only growled a couple of times and we totally ignored her! Might only be a little step, but it feels a massive step as we couldn't do this yesterday. Have weighed out her food for the day and will now give her little bits throughout the day and see if this helps.
Will ask David about getting blood tests done, getting her spayed sooner -- our main problem with this is that we can't actually get her in the car atm, so will be difficult getting her to the vets. Have thought about getting her a muzzel, but not sure how we will get it on her in the first place(!), but also don't want to make things worse for her.............
With regard to behaving on her walks/with other dogs -- she is fine and just wants to go and play with them! She is very responsive on a walk and we have got good recall with her, but saying that, we haven't taken her on a longish walk since Saturday, on David's advice, due to the problems getting her lead on her. We are playing with her in the garden, the back door is always open - I know this isn't ideal and hubby says he's going to take her for a walk tonight - he's stronger emotionally than me, so if she has a go at him, he can cope better than me.