Well, you should know that it is normal to have the situation you have described. When we wear the glasses for the first time, we have to take several days to adjust to them. Generally speaking, the most common symptoms are headaches, eye strain and nausea, and in serious situation it may extend to seeing rainbow colors and spots that are not actually there. But on the other hand, these symptoms what we have said before will usually pass with time. So it should not cause alarm. However, if more serious symptoms occur to you and they exist for a long time, I suggest you should see your optometrist at once. Or it may lead to some eye diseases.