Congratulations on your pregnancy. You should be fine continuing with strength training throughout the duration of your pregnancy as long as you note the following:
At this early stage in your pregnacy, your strength training workouts are fine to do as usual. My only suggestion is that you go for strength maintenance and NOT try to lift heavier than usual weight at this time. The main two reasons for this are 1) You don't want to work in a very high heart rate zone, which can happen when lifting heavy weight. 2) You want to be be careful to not over stress your joints and ligaments since they gradually become softer and softer as your pregnancy progresses(due to relaxin hormone). By the way, this softening process is very normal and is the body's way of naturally preparing for childbirth. As a matter of fact, toward the end of your pregnancy you may find yourself having to lift even lighter weight since your balance and joint stability will have altered quite a bit.
I would also strongly recommend that you begin to strengthen your pelvic floor muscles by doing kegel(internal contraction) exercises throughout your pregnancy(even forever after is great). This will not only help to keep you from leaking urine when you sneeze, cough, or jump (since the baby puts more pressure on your bladder as he/she grows), but will keep your pelvic floor stronger overall(a big plus) since it will become stressed from holding the weight of the baby.
As you get into your fourth month of pregnany, it is no longer recommended that you work flat on your back. For this reason all flat bench work (ex. bench presses) should be done in an incline position and abdominal work is recommended in an all fours position. I'll provide you with ab examples if you need them.
As you end your second trimester and enter your third, you may find your center of gravity shifting, causing you to be a bit off balance at times. During these times, you may have to be more creative finding more comfortable positions to do certain exercises(or eliminating them altogether, if no safe modification is available, until after the baby comes). This is the time to especially take advantage of that spotter if you have one available.
You can continue to exercise right to the end of your pregnancy(of course, modifying more and more as you get closer to the end)as long as you are having no complications.
Good Luck!
!! So glad you are feeling "up" to exercise. Keep us all informed! Your-Friend-In-Fitness, DebbieH 