Eye Power Improvement. Polaroid matter?

I had visited an eye doctor for getting my vision power tested and she gave me the prescription with the spherical power in both eyes different than the ones I had with my current glasses. The cylindrical power was the same but the spherical power got improved by 0.25 in both eyes. I got new expensive glasses made with the updated power. It's been a few days since I've started using them and I'm having slightly blurry vision. I got headaches the first whole day but now thats gone. It feels uncomfortable using these glasses. Is this a common symptom when eye power is changed? Does eye power improve in adulthood (at my age)? Or does the fact that my new glasses are Polaroid matter? I'm not sure if the prescription she gave me is correct because I think I can see better through my old glasses.