Thank you very much for the useful information Amanda.
This can be a spasm (which can last few weeks to months) if not treated appropriately.
The muscle spasms are best treated by means of rest, heating pads application (natural muscle relaxant) and muscle relaxant medications (such as tizanidine or orphenadrine). I can see that you have not been prescribed and muscle relaxing medication nor does you are applying heating pads. Try this---mostly these work.
If they do not, then you would need investigations in the form of MRI of the spine which will give all the essential answers regarding the etiology for this pain you have; like a disc prolapse, or a pinched nerve in the spine.
Yes you can take BRUFEN during breast feeding. This drug is passed into breast milk, but in such small quantities that it is unlikely to harm the baby; especially when not used for longer periods like months or years.
So if you doctor has adviced you to take brufen, there is no harm in taking this and see how you respond to it.
Goodluck and get well soon :)
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