If it doesn't increase evenly I'm pretty sure it should. There may be a mistake in the pattern if it was written correctly by the OP because there have to be 8 increases on each Row 1 (inc row) for it to add up to 150 after the 13 increase rows. There will be 13 increase rows, the original Row 1 (inc row) and then you do row 2 which is even and then you repeat rows 1 and 2 each 12 more times to get to the 150.
There is no way it could increase on one side and not on the other and make a sweater. The OP said for the increase row:
Row 1(inc row):K9 for left front;yo k1 for seam st;yo,k3 for sleeve;yo k1 for seam st;yo k 18 for back;yo k1 for seam st ,k3 for sleeve;yo k1 for seam st;yo k9 for right front - 54 sts.
If it doesn't read this way it should: Row 1(inc row):K9 for left front;yo k1 for seam st; yo, k3 for sleeve; yo, k1 for seam st; yo, k 18 for back; yo, k1 for seam st; yo,
k3 for sleeve; yo, k1 for seam st; yo, k9 for right front - 54 sts.
The way the OP wrote it there are only 7 yarn overs but there must be one before and after each seam stitch at each side of each sleeve for a total of 8 yarn overs per increase row. If you don't have 8 there will only be 53 stitches not 54 as are needed at the end of the first increase row and you will not have 150 after you repeat the increase row a total of 13 times. You would be 13 stitches short and the sweater would be all lopsided. You would only have 137. The way she wrote it left out an increase (yo) on the sleeve portion each time, so the sleeve portion would be 13 stitches short on that one side. Is that what you are talking about?
Read the other posts I gave. I'm pretty certain I'm right about the way this works.