Skipping a month.

I was prescribed Loestrin almost 4 months ago. The doctor gave me 2 trial packs to take before filling my prescription. Upon starting the bc pills, I experienced quite a bit of breakthrough bleeding in the 1st month. This slowed to almost a stop the 2nd month. After having my period, I should have filled the prescription for the 3rd month, but due to stressful, long work days, I failed to do so. I wound up skipping the whole month of pills [really bad I know]. I waited till after my period, and started the next month of pills. I am about a week away from finishing the pack, but I've been having breakthrough bleeding for about a week straight now. Not as heavy as a normal period, but a little more than spotting. I'm having cramps and feel a little light headed as well. Is this normal? Is it just because I've basically started the whole process over again?