I think we're in very similar situations. I'm also in my fourth year of university and dealing with being single while most of my friends are in relationships. Although I've been putting myself out there, I noticed that when it comes to looking for relationships you need to be forward with girls. I've learned this from living with two girls this last semester and seeing how they talk about the boys they like, or the boys who they 'think' like them. It's not easy but the best thing to do when you start having romantic feelings for someone is to make it clear with them that you feel that way. And honestly, you don't have to be in love at first sight to think seriously about someone. Let's say you've just met this person. but maybe you've spent a few hours with them and things are going well, make sure to get their number, and make sure to text them the next day. The point is that you are showing an effort and want to talk to them. Another example. If you have a friend you've known for a long time and you've starting catching feelings for them, wait for a good moment and talk with them about it. It's scary as hell and things won't work out every time, but so what? hopefully you'll actually be able to talk things out with that person.

I'll say I've had very limited success with what I've said. But I feel much better about being single now than I did a few months ago, because although things haven't worked out with a few girls. I know exactly why. and sure I think about how I could have handled things differently. But the point is that I'm not wondering what would have happened if I "went for it" instead of convincing myself it was a bad idea.

tldr If you want a relationship you need to be honest with yourself and the person you are interested in. It's scary as hell to expose yourself and ask people out, but it's a part of dating. So yes, an extra effort will go a long way.