Talk to Gynecologist on Period Altered

I had to take an emergency contraceptive pill about six months ago. And my period has changed ever since. Previously my period was nearly painless. Cramps only on day 1 and only for a couple of hours. It was 3-4 days max. The flow was moderate. I did not have a lot of spotting. But now my period has become very painful and remains that way throughout. The flow has become slightly heavier than it was. And the duration is now 5-6 days and I keep spotting until the period ends. I have been very depressed and anxious. My hair fall has also significantly increased. I should also mention that I am underweight for my height and have been a vegetarian for more than two decades. Could this be the pill? Has it caused some sort of hormonal imbalance? Will my period ever go back to the way it was? What can I do to get it back? Should I get checked?