MMRV Vaccine and Legs Problem?

My poor little Caitlyn is now sick! :(

We brought her to have her MMRV and Pneumococcal injections last last Saturday... and last Friday, she had a slight fever (38 degrees), so I gave her Paracetamol before she sleeps. Luckily, the next day she was alright and as cheerful as usual, though a little bit low appetite. So we still brought her to a birthday party (I will tell you about this in another post)

Anyway, yesterday (Monday), in the morning she was quite alright, still low apetite but she can walk around, jump jump jump, etc like normal. Suddenly after waking up from her afternoon nap, she started limping, and afterwards, started crying whenever she wanted to use her right legs! It's like it's very very painful for her :(  So in the end we carry her around as she didn't wanna walk or move much....

I called the PD and asked whether it's related to the MMRV that she took a week earlier, but he said no... Though some from the internet had exactly same problem after their babies took MMRV vaccine..

And though she had a nap for quite long, she still went to bed early yesterday (whereas normally, it would be a more than 1 hour battle to bring her to sleep at night). And the poor little girl normally loves to sleep sideways, and she CAN'T lift her legs to change position to sideways! So she cried the whole night (maybe every 30 mins or so) coz she can't move her legs.. sigh.........

We were thinking to bring her to PD today, but miraculously after she woke up from her night sleep, she walks normally again! And can even walk fast like normal. Hmmmmm... I hope the problem won't come again..