4 YEAR OLD WITH EXTREME HEADACHES, MRI CLEAR. 2ND OPINION?

[SUFTY21]

HELLO,  my 4 year old son is having extreme headaches for nearly 18 months now, they first started off as a pain in his brain he would say.. over the last couple of months they have become more frequent longer in duration and has had alot of vomiting on occasion. friday gone he received an mri, as a mother i went through scrutinising the scans even though i had no idea what i was looking at. i was convinced there were several slight upsets.. (but this is what happens when you google) before the mri i had been told migraines (without any testing) is it normal for migrains to start at 2.5years of age? he had a severe chronic headache on monday evening, threw up everywhere and refused to move, as i had not received results yet i didnt go to a and e as i thought i would be fobbed off again... i have alot of images and i have even taken videos to try show what he is experiencing is not normal..? could anybody shed any light on migraines etc or do you think a 2nd opinion is warrented? i also forgot to state it showed movement on the mri stated on report but clearly not enough for them not to give the report. thank you xx