Please give paracetamol after the immunization especially if there's fever.

If swollen, you should apply ICE PACKS (you can wrap ice blocks in handkerchief) and put on the area intermittently and give Paracetamol.

If you are following the Nigerian immunization program then what you will be given at 12 months is oral vitamin A, but there are other Non-NPI vaccines like chickenpox and meningococcal vaccines which can be gotten from private hospitals.

Yes

Yes she can go ahead and take all the missed vaccines. That is what we call catch-up immunizations.

My doctor once told me to avoid yellow fever vaccination as a breastfeeding mother. In his words , she said - Until more information is available, yellow fever vaccine should be avoided in breastfeeding women. However, when nursing mothers must travel to a yellow fever–endemic area, these women should be vaccinated

Yes, you can. HBV is the Hepatitis B Vaccine. It is one of the 5 vaccines contained in PENTA Vaccine. PENTA Vaccine is a combination of Diphtheria, Pertussis, Tetanus Toxoids, Haemophilus Influenzae type B and Hepatitis B Vaccines

Babies are supposed to take Vitamin A from 6month and continue every 6month till the baby is 5years. Meningococcal vaccine (MCV) too is from 2years

There won't be any problem, there is a month interval btw the 1st and 2nd dose.
Congratulations sis. Baby dust to all TTC