Estrogen can increase due to a large number of influences. Without testing your tren and knowing everything you do and eat, it's hard to tack down the cause of elevated levels.

300 mg of test is enough to cause higher E2 levels and without knowing your before, during and after blood work it's all a guessing game.

You ASSUME the test is not estrogen laced, you ASSUME the E2 level is not related to your test dose (I was over 300 on 200mg of test C). You wanna find out? have your tren tested, run it with no test and then do bloodwork. Otherwise just take measures to control your E2.