Thanks for writing in to Healthcare Magic!
Yes you can take diclofenac
but you should rather keep a more safe drug at hand like a paracetamil tablet or Ultracet
to be taken as required.
Diclofenac can be given to lactating mothers with precation means it is not extensively studied in this population.
If you have any further query please let me know I would try to answer it for you.
Wish you a great health!