Yes, I can agree with also doing micro-needling first then filler, but if filler is already done then wait 2-3 weeks before treatment of micro-needling. Should not affect the filler.
I recommend adding prp to microneedling in order to improve it's benefits for rebuilding collagen. Other alternatives would be: Sculptra, lasers, radiofrequency devices and ultrasound would be very useful to help rebuild your naturally lost collagen and get lifting and better texture and tone...
Thank you for question. It is difficult to give you an answer without any photos. However, it is common to have some itchiness, redness and swelling after microneedling treatment. If you still have concerns follow up with your treating physician.