Problems uploading media file

Yesterday, I could upload with no problems. I made one tiny change to the jpeg and needed to upload it again so the graphics were right. The file size is just 354KB.
If I use the bulk uploader, it uploads to 100% then gets stuck. Sometimes it says I have reached the max upload of 10MB…… This can not be the case!
I have disabled plug ins. Enabled them again.
I do not know how to access the root directory to increase the php (I don’t understand what that is anyway). I need help……