Last night my boyfriend penetrated me but did not pre- or ejaculate. I am on Tricyclin Lo birth control pill. What are my chances of getting pregnant?

No.

Pre isn't something your boyfriend can control. If he was able to enter you, then there was pre. Pre is the fluid that makes his penis slippery so that he can have sex with you.

In other words, yes, you could be pregnant. You'll have to wait until your next period is due. If yo miss it, wait 2 weeks and test using first morning urine.

No.

Care to clarify? No what?

There is a chance, and yes if he entered you there was most likely early fluids, he has no control over them.

You are on the pill, do you take it perfectly, never miss any days, normally same time every day ?

Have you been on the pill over 30 days ?

The pill says it is at least 99 percent effective. So I guess that gives you a 1 percent chance.
But you know it is possible that you will be that lucky winner,
Millions buy lottery tickets with a one in ten million chance of winning and guess what, someone wins,

So your one in a 100 chance may be that lucky winner this time

The pill is one of the best forms of birth control, I do agree, but it's only 99% if taken correctly. That means taking it every day, at the same time every day. If you don't follow that criteria every single day, the percentage rate for effectiveness drops.

It's always best to use at least 2 forms of birth control. We have a few members on this site that not only used 2, but 3 forms of birth control, all used correctly, and still got pregnant. So yes, there is a chance.