Her behaviour in itself is not bad. Why can't she text whomever she wants whenever she wants?

Checking her phone whilst your putting on a condom imo is bad and I would address that calmly and maturely, but that is more of a compulsive addiction behaviour that a bad/disrespectful behaviour. It also means that you are not doing foreplay correctly my friend...

The problem here is that you seem to be obsessing over this one girl. Yes it's great to have a healthy and committed relationship but this is not healthy. You should have mutual respect for each other, not be seeking to "punish".

Firstly you need to get over your hangups and trust her. Because if you don't trust her then get out of the relationship but if you do you need to have a little faith in her.
The best way of doing this is making your own life interesting and awesome so that you have other choices of things to do other than fascinate over what your girlfriend is doing. Take up hobbies, go and see live bands or collect stamps. Something that will make you stop checking whether your girl is online and also give you the option of saying "hey not tonight, I'm busy"

Secondly you are not alpha if you are searching for a way to be "alpha" and assert it. It is something that is there or it isn't and in part it isn't something you can bring to a relationship.